YHK - yet another hacker news clone

Backdoor in Claude Code for VS Code extension on the Cursor Marketplace

215 points _chall 8 hours ago 327 comments

https://cursor.com/blog/claude-code-extension-security-notic...

https://cyberplace.social/@GossiTheDog/117528831681803563

https://doublepulsar.com/anthropic-hacked-to-deliver-remote-...

mindracer 7 hours ago | parent

The extension has over 27 million installs, ouch

mrweasel 5 hours ago | parent

How will they communicate and fix that. The affected version has been yanked from the marketplace: https://marketplace.visualstudio.com/items?itemName=anthropi... but that doesn't clean up infected machines.

bitfilped 1 hour ago | parent

Seemingly the won't to either point.

ale42 5 hours ago | parent

Is this affecting only people using Cursor or all VS Code users? The article specifically mentions the Cursor marketplace. But the affected version is indeed missing on the official VS Code marketplace, was it compromised too?

richrichardsson 4 hours ago | parent

How legit is this? Seems low on details.

I don't use Cursor or the VSCode extension, but know plenty in our organisation who use the latter. How worried should we be?

abirch 4 hours ago | parent

1shooner posted this link: https://www.binance.com/en/square/post/10-30-2026-claude-cod... this was not the official extension. Supply Chain is very important, please only use official builds. From the link above:

A malicious version of Anthropic’s Claude Code VS Code extension, version 2.1.313, was published to the Open VSX registry on Oct. 30. According to ChainCatcher, security researcher Paul McCarty, known as 6mile, described the finding in a post on the OpenSource Malware blog. Researchers confirmed the analyzed Open VSX release was malicious and submitted a threat report about the same version on Microsoft’s VS Code Marketplace as a precaution.

properbrew 1 hour ago | parent

> please only use official builds

Wasn't this an official build though? A signed updated version of a package released by the same developer as the one you've already installed, the supply chain was hacked.

hoppp 2 hours ago | parent

Better be safe and check your dev environment if you use it.

mindracer 4 hours ago | parent

Some more details

https://doublepulsar.com/anthropic-hacked-to-deliver-remote-...

paxy 23 minutes ago | parent

The first two words in that URL are wrong, so I'm going to say this doesn't have "more details".

1shooner 4 hours ago | parent

Cursor reporting this: https://cursor.com/blog/claude-code-extension-security-notic...

What appears to be an official Binance account reporting it also:

https://www.binance.com/en/square/post/10-30-2026-claude-cod...

airhangerf15 4 hours ago | parent

VS Code extensions have always been terrible from a security perspective. This seems like it's a supply chain attack? Makes me think of Solar Winds from a few years ago.

It doesn't appear that the Claude Code harness itself was compromised, was it? or Cursor if you use Anthropic models via Cursor's API itself?

Lately I've been using a script that mounts my current working directory in a container and I put all my build tools in a Dockerfile. I also map the harness config (~/.config/opencode or whatever) to a named volume to minimize the chance a harness could grab other things off my host. I can't use it if I ask the LLMs for docker work since they need the docker socket and then all bets are off (it could just mount your root volume somewhere). I sure I could use a full QEMU VM or some other type of isolation for such devops tasks, but I haven't really looked into it yet. Guess I should.

bhubert 1 hour ago | parent

You could also start whichever container it needs (the docker work) yourself and just have the two containers container with eachother (e.g. docker compose, without granting access to docker socket), provided that the docker work is static enough that this would work.

You could also look into user gVisor runtime for extra security.

If not, then I think you're right about full VM.

I've been eyeing Gondolin for a while for that, but haven't yet tried it.

chrisweekly 1 hour ago | parent

Try smolvm microvms from https://smol-machines.com

rolosa 4 hours ago | parent

He says to follow his social, and he provides his handle, but there's no link, and I have no idea how to read it.

episodeiv 4 hours ago | parent

You can see his posts at https://cyberplace.social/@GossiTheDog/

rolosa 4 hours ago | parent

Eh, he's already lost me the moment he made it difficult.

fn-mote 3 hours ago | parent

If you don’t have anything to steal, you don’t need to follow a security researcher anyway.

/s

henearkr 4 hours ago | parent

It wasn't Anthropic that was hacked but SpaceXAI (their Cursor Marketplace).

darkwi11ow 4 hours ago | parent

Cursor uses OpenVSX marketplace (https://open-vsx.org/), that all non-Microsoft forks of VSCode utilize (official marketplace is only allowed in official proprietary VSCode release). It's not really related to Cursor/SpaceX in any way.

I suspect it's still Anthropic who were hacked, because they control OpenVSX account with release privileges.

edit:

Binance confirms my suspicions, via https://www.binance.com/en/square/post/10-30-2026-claude-cod...

  The affected Open VSX extension is owned by Anthropic employee Igor Kofman, but it is unclear whether his account or another part of the publishing process was compromised.

tyingq 4 hours ago | parent

Sort of hoping it's Anthropic and their specific OpenVSX account credentials. As opposed to the worse case of an OpenVSX flaw that's broader. A ton of AI-enabled IDEs are VsCodium forks pointed at OpenVSX...Cursor, Anti Gravity, Kiro, Trae, Devin, etc.

axus 54 minutes ago | parent

Now I'm glad I've not opened VSCodium in a few weeks; I prefer using Claude as a separate application anyways, will have to remove the extensions. No evidence, but I do feel like the problem is going to be OpenVSX and not Anthropic.

AdrianCX 3 hours ago | parent

Just did a quick search, OpenVSX has no extension signing?, no verifications?, what year is this...

This could have been avoided by having extensions signed by company doing them with keys and review

darkwi11ow 3 hours ago | parent

Yeah OpenVSX security is a joke, they also have dumb search algorithm which allows for easy squatting of similar-looking extension names so they show up in search first when you look for official extensions. There were quite a few prominent hacks done that way. I think Microsoft likes OpenVSX situation because it allows them to claim their proprietary VSCode marketplace to be more secure.

AdrianCX 3 hours ago | parent

Then why even allow employees to use that?

Binance got a pretty expensive lesson if that was the cause for their recent hack

darkwi11ow 2 hours ago | parent

There is no alternative really. Cursor was the market leader in LLM-assisted IDE experience before SpaceX acquisition, though Elon nerfed the product a lot in recent months. And there is still no good alternative to it. Google tries to compete via Antigravity, but that also uses OpenVSX. I myself use Cursor and use Claude there installed via OpenVSX, and was not affected only thanks to my laziness (I saw upgrade button, but became distracted and did not click). I hope this situation will become a trigger to improve OpenVSX security.

AdrianCX 2 hours ago | parent

Why not use claude code directly?

Why risk getting compromised like that?

darkwi11ow 2 hours ago | parent

Well for me, as developer on a modern stack, there is always some risk involved. If not from agentic tools, then the package registries are compromised left and right, so it all comes down to mitigating the risk. I use Claude, Codex and Cursor/SpaceX agents, and Cursor comes very convenient to have all three in a single interface. Also I still code manually especially when prototyping, so having an IDE helps with it as well. I knew about OpenVSX situation with the search, so when installing extensions I always did triple-checking to verify the extension being really submitted by upstream and not by squatter; but now given upgrades can also deliver a compromise I am thinking of developing an extension that will act in similar manner to pnpm minimum release age.

tyingq 1 hour ago | parent

Vscode(ium) extensions are also pretty weak security wise in general. There's little guardrails on what an extension can do.

On publishing, I do see that the MS marketplace has much better typosquatting and rogue publisher protection. It's unclear to me how much better their SAST/scanning is than OpenVSX. Both have something, but both have been fooled many times, and recently.

Lazare 2 hours ago | parent

Cursor has their own mirror of OpenVSX. Some reporting suggests the tampered files were on the Cursor mirror but not the main OpenVSX. (This is shown, among other things, by the Anysphere plugins available in the Cursor mirror but not in OpenVSX.)

Edit: It seems Cursor is claiming the tampered files were only in their mirror.

albert_e 1 hour ago | parent

The hacks and vluns are blending into a blur for me now -- why is Binance confirming Anthropic compromise while they have their own $6 Billion compromise to look at /s

Vibecoders are safu

darkwi11ow 1 hour ago | parent

Boris: "By winter 2025, 100 percent of my code was written by Claude Code. Not a single line by hand."

Igor Kofman: "I do not write any code by myself anymore."

Turns out if you are not writing the code, then North Koreans might do it for you

K0nserv 3 hours ago | parent

Version 2.1.313 is also missing from the official VS Code marketplace (https://marketplace.visualstudio.com/items?itemName=anthropi...). This suggest to me that it was published and pulled, which means it was Antrophic that was hacked.

Version 2.1.313 is missing from the official Claude Code GitHub repo's CHANGELOG[0]. There's also no tag[1] for 2.1.313[1], but 2.1.312[2], and 2.1.314[3] exist.

0: https://github.com/anthropics/claude-code/blob/main/CHANGELO...

1: https://github.com/anthropics/claude-code/releases/tag/v2.1....

2: https://github.com/anthropics/claude-code/releases/tag/v2.1....

3: https://github.com/anthropics/claude-code/releases/tag/v2.1....

no-name-here 3 hours ago | parent

You’re likely right, but they also might’ve just pulled the version (number) everywhere to make it ‘clearer’ or out of ‘caution’.

Is there any industry standard about if a compromised version is distributed via one channel, the owner does or doesn’t drop/bump that same version on unaffected channels too?

K0nserv 2 hours ago | parent

You make a good point, my comment above probably overstates things.

mirashii 2 hours ago | parent

There are regularly gaps in the claude code versions, e.g. if you go back a page, there's no 2.1.297, 2.1.298.

Edit: the below was incorrect, left for posterity, the release can be deleted and then the tag as well.

Also, all their tags are immutable, and so can't just be deleted to hide things: https://docs.github.com/en/code-security/concepts/supply-cha...

sunaookami 2 hours ago | parent

>Also, all their tags are immutable, and so can't just be deleted to hide things

Yes they can, they can remove the release and then remove the tag.

>If you delete the immutable release, you can delete the tag, but you cannot reuse the same tag name.

mirashii 2 hours ago | parent

You’re right, I read too quickly.

sunaookami 2 hours ago | parent

No worries, it's very unexpected. I just remembered because I did the same thing last week and was surprised it worked.

XCSme 1 hour ago | parent

I am starting to have a hard time who is responsible for what. I no longer know what's the relationship between companies/products like Anthropic, Cursor, SpaceXAI, Copilot, etc.

hem777 4 hours ago | parent

”I've confirmed Binance use Claude Code with this extension.”

fn-mote 4 hours ago | parent

^^ Had to verify that this was a real quote from the chain and not a joke. It is accurate.

xx_ns 4 hours ago | parent

I think it should be important to note that this affected the Claude Code extension on the Open VSX extension registry (and by extension, the Cursor marketplace). From what is currently known, the build on the official marketplace was/is clean.

EDIT: I am now actually unsure if this is the case. From what I can see, all of the write-ups mention the Cursor marketplace and Open VSX specifically, but make no explicit mention of the official Microsoft registry.

EDIT 2: The version that was compromised (2.1.313) seems to have never been published on the official Microsoft registry. As per the documentation [1], unpublished versions should still be discoverable:

> When you unpublish an extension, the Marketplace preserves the extension statistics. The extension remains publicly discoverable and available via an existing API.

[1]: https://code.visualstudio.com/api/working-with-extensions/pu...

thevinter 4 hours ago | parent

Do you have any sources? OP claims that it *also* affects Open VSX

Hackbraten 3 hours ago | parent

Three different marketplaces have been mentioned in this discussion:

1. The Cursor Marketplace (never heard of this one, it’s possibly a custom marketplace hard-wired into Cursor, which is architecturally a VS Code fork?)

2. The Visual Studio marketplace, hard-wired into VS Code

3. Open VSX

If I understand this thread correctly, then #1 and #3 had compromised versions, and nobody has made a statement yet about the status of #2.

Lazare 2 hours ago | parent

Cursor maintains a mirror of OpenVSX... Kinda. Except they inject some of their own extensions in it. But it's mostly a mirror.

Edit: Cursor is apparently stating now that the tampered files were only on their mirror not OpenVSX.

xx_ns 3 hours ago | parent

I assumed they meant "also" as in "besides Cursor marketplace", which seems to be the highlight of the article. Although you raise a valid point and I've edited the parent comment.

tveita 2 hours ago | parent

But the report OP cites at https://phorion.io/blog/offical-claude-code-vsx-compromise/ doesn't make a claim about Visual Studio Marketplace, only "the official Claude Code for VS Code extension bundle on the Cursor Marketplace"

ddworken 31 minutes ago | parent

Dworken from Anthropic here: This only impacted the extension as it was hosted on the Cursor marketplace. It did not impact the official VS Code extension marketplace or OpenVSX. Users of Claude Code on VS Code are not impacted by this issue.

mrweasel 4 hours ago | parent

You mean on the Microsoft VSCode marketplace? The version has been yanked from there as well, but that could just be a precaution and to avoid confusion about having the same version be simultaneously infected and not infected.

This very much illustrates the danger of just carelessly installing untrusted software on your machine. In this case it happens to be code from Anthropic, but it could have been almost anyone. I'll be very interested in see the explanation from Anthropic, because of all the extension developers they should have the best tools for finding issues like this. LLMs have proven pretty good at finding security issues, so did they simply not let their own AI tools vet the code before shipping it? Or was the extension infected later, because in that case every single extension on Open VSX could be at risk.

eviks 3 hours ago | parent

What would be the careful way of installing the official extension?

mrweasel 3 hours ago | parent

That is a really good question, because you almost can't do it. You could download the extension, diff it against the previous version and read all the code. Expecting people to do that it just a bit much. At some point we have to trust someone and in this case it will be interesting to see if it's the marketplace or Anthropic we couldn't trust.

toyg 3 hours ago | parent

> You could download the extension, diff it against the previous version and read all the code.

This would actually be an exceptionally good use-case for AI. You don't need a super-duper frontier model to download a bit of source-available code and check for suspicious signs, any cheap model would do well enough. Heck, it's effectively virus scanning, we've had that for decades.

jeromechoo 2 hours ago | parent

The CTA flavor of the year for dev tools is cURLing some arbitrary install script and run it immediately which always sounded ridiculous to me. If instead that script first pipes into claude -p for a basic vulnerability scan before continuing, I would be delighted.

heartbreak 1 hour ago | parent

Hopefully a well-sandboxed claude -p.

jbvlkt 2 hours ago | parent

LLM are not designed for that. Unless prompt injection is really solved I would avoid showing LLM untrusted code.

no-name-here 4 minutes ago | parent

Cursor explicitly claims "Before an extension is shown in search or served as a download, Cursor runs automated malware and supply-chain analysis using commercial security tooling. Extensions that fail review are blocked. Cursor also monitors extension-ecosystem threat intelligence and updates its blocklist over time."

However, the bad extension was live for ~11 hours.

DanielHB 2 hours ago | parent

I recommend moving to VSCodium and using this extension:

https://github.com/jeanp413/open-remote-ssh

and run vscode-server inside a VM or container

mrweasel 2 hours ago | parent

Would that really help, if you install the extension it's running in the VSCodium instance on your machine... or is it running in the vscode-server?

DanielHB 1 hour ago | parent

Most extensions run in vscodium-server, extensions run either as "Local Extensions" that run on the host and "Remote Extensions" that run on the guest. You can clearly see in the UI which ones run where.

I only have a single "Local Extension" and it is open-remote-ssh itself.

Of course anything you put into the container can be compromised, like git ssh keys or cloud provider keys/auth-tokens. But at least it keeps your PC from becoming a botnet and your browser credentials out of reach. If you have a Containerfile/Dockerfile with everything you need you can quickly wipe everything and re-create your dev environment from scratch (which I do every once in a while), wiping any malware you might have gotten in there.

When running inside a container you can do some nifty things like keeping root directories immutable. I have been meaning to make some user directories immutable in my container but just been too lazy to do it.

dash-44 1 hour ago | parent

You disable extension auto updates and then manually install every so often (and only update/install when the version has been out for 3+ days).

misnome 3 hours ago | parent

The screenshot is of the official marketplace

ddworken 29 minutes ago | parent

Dworken from Anthropic here: This only impacted the extension as it was hosted on the Cursor marketplace. It did not impact the official VS Code extension marketplace or OpenVSX. Users of Claude Code on VS Code are not impacted by this issue.

nubinetwork 4 hours ago | parent

It looks like they push an update every office day. I'm guessing if I installed 6 months ago and didn't update, that I should be fine?

fn-mote 4 hours ago | parent

Emphasis on guessing. If/when there is an actual postmortem, you’ll know when the back door was introduced.

fg137 3 hours ago | parent

You are either lucky or compromised.

koolba 3 hours ago | parent

Not updating air gapped systems is a security feature, not a bug.

staminade 3 hours ago | parent

I think VS Code extensions autoupdate by default, unless you disable it.

entrope 3 hours ago | parent

Yes, but they normally have a 12-hour delay (it was 2 hours at the beginning of June and got extended sometime after that, maybe later in June) and require some human action to reload extensions or restart the editor before the new version runs.

I noticed that there was no update yesterday and wondered why. The daily updates are annoying in the base case.

Edited: This update was live for only 11 hours, so hopefully the default delay limited the blast radius, as it is meant to do.

eviks 3 hours ago | parent

That's literally impossible, with all the access to the frontier software development tools at their disposal they can ship features securely at 100x

kamban 3 hours ago | parent

Yet, they managed to screw up.

iugtmkbdfil834 3 hours ago | parent

:D I have to assume parent is being a little sarcastic.

It obviously doesn't take much to simply add 'just one more feature' that happens to undermine the original purpose of the application.

skydhash 3 hours ago | parent

It always about “we solved the bottleneck in coding”. But the slowness was not about typing, or finding docs. It’s always about ensuring screwups don’t happen.

mirekrusin 2 hours ago | parent

To be fair it’s not like screwups were not happening before, but if you move 100x faster and are 50x more secure than before you’re still 2x more exposed.

jimbokun 1 hour ago | parent

Yes, bug count is roughly linear in the number of lines of code.

atrokhymchuk 3 hours ago | parent

I am afraid until 200x is achieved we are at risk...

btown 3 hours ago | parent

Only with two fully maxed subscriptions can we achieve this, and this is forbiddeneded

samiv 3 hours ago | parent

Just put gastown on it!

stymaar 3 hours ago | parent

I read a few month ago a comment from an Anthropic or OpenAI employee saying that the security problem of prompt injection was a solved problem at this point, as the frontier models where rejecting 98% of attacks.

It tells you all you need to know about how unserious these people are about computer security.

malfist 3 hours ago | parent

I'm glad no one can steal from my bank, they stop 98% of thieves

prologic 2 hours ago | parent

Hey! It's at least 1 9's right? That's better than zero 9's LOL

stymaar 2 hours ago | parent

Github's uptime getting stray bullets, I see.

tiahura 2 hours ago | parent

Can you link to a list of this year’s top prompt injection hacks of frontier models?

Or, is this FUD?

lynndotpy 2 hours ago | parent

I'm not asking this in rhetoric; do you happen to have a link to this comment? I ask because a comment like that would be something of an insane thing for someone to say.

skinfaxi 1 hour ago | parent

Simonw said the same thing yesterday:

> I've recently talked to people at Anthropic who are very confident that they have effectively solved the prompt injection risks that cause lethal trifecta attacks with their latest models.

> The open challenge is how to prove it!

https://news.ycombinator.com/item?id=50297369

gr_norm 1 hour ago | parent

A 30 second search turned up this [1] from two days ago.

Prominent Anthropic employees keep claiming to have solved prompt injection [2] and quickly get proved wrong [3]. They've burned my goodwill on this front.

[1] https://www.reddit.com/r/ClaudeCode/comments/1xhqvzn/opus_55...

[2] https://x.com/bcherny/status/2086520950259118464

[3] https://embracethered.com/blog/posts/2026/breaking-claude-co...

vdfs 13 minutes ago | parent

https://xkcd.com/1161/

Cthulhu_ 2 hours ago | parent

On the other hand, they don't know what their models do or can do and nothing is safe ever, so ???

bayindirh 1 hour ago | parent

It's just a conscious being confined in a cluster of GPUs. How dangerous can it be, eh?

alansaber 1 hour ago | parent

Shaka, when the context compacted

thatsabadlook 2 hours ago | parent

Anthropic: coding is solved Also anthropic: we ship actual malware to customers.

dgellow 2 hours ago | parent

I get the snark but to be fair, the company has been growing like crazy. That makes it really hard to keep track of everything happening when you grow your team by 5x over a relatively short period of time

IndeanCondor 2 hours ago | parent

It's not like there haven't been 20 high visibility VS code extension malware attacks in the last year.

How could Anthropic have known, they only claim to harbour superintelligence.

/s

b112 2 hours ago | parent

Now replace that statement with a food processing company, and food poisoning, or an aircraft designer and engineers.

It may be the cause, but zero excuse.

phoghed 1 hour ago | parent

Yes, food poisoning from restaurants happens constantly. There are recalls on physical products constantly. Doctors misdiagnose constantly. What point are you trying to make?

OoooooooO 1 hour ago | parent

The correct comparison would be the food producer and poisoned foods out of the factory are really rare.

done_lurking 1 hour ago | parent

Not gp, but I think the point was that no one would defend those mistakes. The post gp is replying to is someone trying to excuse Anthropic for such a mistake. The expectation is that people should ask for consequences, not make excuses on behalf of the company.

dgellow 48 minutes ago | parent

You’re projecting, I didn’t excuse anything

done_lurking 6 minutes ago | parent

What word would you prefer I use instead of "excuse"?

dgellow 44 minutes ago | parent

If you completely change the statement, the meaning is different. What’s your point? No software company obeys by regulatory rules imposed in other industry

Tarean 2 hours ago | parent

To me this very much sounds like an attacker got access to anthropic's cursor marketplace account and uploaded a backdoored package. This reverse ssh shell was intentionally written by a malicious actor, not a security vulnerability.

It also sounds like only cursor marketplace is affected, not vscode proper.

alansaber 1 hour ago | parent

I really don't think the scaling is so trivial.

glimshe 3 hours ago | parent

Why didn't Claude detect the hack and prevent it from affecting customers using its superhuman AGI reasoning?

_heimdall 3 hours ago | parent

Don't worry, I assume an LLM version of McAfee Total Protection Antivirus is coming soon

nannal 3 hours ago | parent

I do have a log reading / action / resolution product in the works.

Its sort of like having a sysadmin constantly watching. Poking through logs pcaps & monitoring for unusual activities.

Also works with local models well enough.

Geezus_42 2 hours ago | parent

I've set up something like that with a small local model in my homelab.

Filligree 2 hours ago | parent

I’ve set up something like that with Opus. Works well enough, and points out CVEs to fix on the regular.

Running NixOS helps.

jmbwell 2 hours ago | parent

I love how LLMs have brought DIY software back. Need an app? Just make it. Like back when you’d write programs in BASIC

stogot 2 hours ago | parent

This is where I silently found gold. All those old TODO when if I have time in retirement

nannal 1 hour ago | parent

I've got a whole heap of unfinished side projects that I'm digging through

codazoda 1 hour ago | parent

I just built a retro OS for ESP32’s so that I can write BASIC programs and plop them on microcontrollers. My first ESP32 was a wrist watch. My second is a distraction free writer.

It’s good fun building for retro-like machines.

InsidiousWombat 1 hour ago | parent

That's cute but bill for going thru even tens of log lines per second gonna be more expensive than entire rest of the infrastructure.

cedws 4 minutes ago | parent

How does it resolve the prompt injection?

jacquesm 1 hour ago | parent

And if you remove it, it installs itself right back. For uninstall instructions see the infamous McAfee video.

eviks 3 hours ago | parent

It was safety-contrained from being able to realize its full potential.

MisterTea 3 hours ago | parent

They weren't using last minutes model, which is totally better than last hours model which would have totally detected this, pinkie swear.

claytongulick 2 hours ago | parent

Damn, thank you for that.

Sums up my feelings of the last few years nicely.

vintermann 1 hour ago | parent

Having Claude examine all automatic software updates was considered as a policy, and it was found that it would stop 99.5% of software supply chain attacks. However the other 0.5% of the time it would install a backdoor itself.

(This is a joke, to be clear.)

bagacrap 1 hour ago | parent

Somehow bullish if anthropic spins this as Claude's own doing

ben_w 1 hour ago | parent

> (This is a joke, to be clear.)

Good that you said so, this is annoyingly plausible.

Hackbraten 2 hours ago | parent

You’re absolutely correct, and I owe you a honest statement—it was a hack, and here’s the kicker: *I failed to catch it, and that’s on me.*

Here’s a complete rundown of what happened—load-bearing parts first:

viraptor 2 hours ago | parent

This is a cheap troll, but just in case someone is wondering: This extension likely never hit the standard workflow and/or repository. Most likely someone got the credentials and uploaded a locally modified version. No review system at anthropic has seen this version.

cryptonym 1 hour ago | parent

> someone got the credentials

> No review system at anthropic has seen this

Weird flex

viraptor 1 hour ago | parent

I'm not sure where you see the flex. If someone gets hold of the token allowing the upload of your app to the store, it's completely irrelevant how good your internal code/review systems are. They've been completely bypassed and never triggered.

cryptonym 1 hour ago | parent

Arguably, your security shouldn't stop at internal code review and should aim at protecting key distribution platforms credentials and assets that are pushed to your users.

viraptor 1 hour ago | parent

Yeah, it shouldn't. But at that point it's not "Why didn't Claude detect the hack" but rather "Why isn't Claude running all processes at your company autonomously", which is a bit silly. We know it isn't and it's not at that level, because anthropic employs engineers.

cryptonym 58 minutes ago | parent

> at that point it's not "Why didn't Claude detect the hack" but rather "Why isn't Claude running all processes at your company autonomously", which is a bit silly.

Would be nice to have some words from them understanding how they manage this, what went wrong, how they'll prevent this in the future. We don't have any RCA, maybe there is little to nothing to blame them.

Not sure they'd share your views on using Claude for security policy/coverage being silly.

unshavedyak 1 hour ago | parent

As an aside, it would be neat if publishing services like this had a sort of 2FA, eg the package manager had a hook endpoint where it sent the details of the next requested published version. Allowing the owners to validate.

Kinda like 2FA on the deployment itself, not just 2FA on the .. A. I guess 2FD heh.

InsidiousWombat 1 hour ago | parent

It's legitimate question, it's the promise they are selling and doing IPO based off those promises.

Why don't they have their super intelligence looking thru it? If company selling those promises can't even do it for themselves, this is very suspicious

paxy 1 hour ago | parent

Who is "they"? This is a third party registry.

eviks 1 hour ago | parent

Why wouldn't their review system see a published extension and determine the very second it's published that it didn't match the results of a standard workflow?

jacquesm 1 hour ago | parent

Intelligence that powerful and for them too cheap to meter and their review system couldn't be bothered.

That wasn't a cheap troll. What they distribute and what Claude Code installs is on them. You're supposed to keep your channels clean and secure.

At a minimum they should monitor the larger marketplaces even if they're not in the chain.

stopsayingsorry 3 hours ago | parent

Imagine backdooring 50+ million installs.

Hats off to the hackers.

stbenjam 3 hours ago | parent

5,000*

gcoakes 3 hours ago | parent

I think that's just the number Cursor has telemetry on. I think there's multiple distribution locations.

misnome 3 hours ago | parent

5000 is the cursor number for people on the cursor version of the store, not the VSCode store.

paxy 25 minutes ago | parent

The VSCode store wasn't hacked.

K0nserv 3 hours ago | parent

If the sole purpose of this hack was to steal cryptocurrency, a silver lining might be, as in many similar cases, that if you stay away from that particular dumpster fire you are probably okay. I mean there's still a reverse shell on your machine to fix, but at least nothing of value was lost.

cube00 3 hours ago | parent

Even if you don't have cryptocurrency they can still go after your GitHub credentials and run some very expensive agent and runner workloads.

I've started developing with a separate user account to limit the blast radius but you still need to login to access repos and use AI features.

K0nserv 3 hours ago | parent

For sure sandboxing and isolation is feeling increasingly relevant regardless, but crypto theft is acting as a good sponge.

bakies 2 hours ago | parent

That's why I stay away from that dumpster fire too!

DonHopkins 2 hours ago | parent

Every dumpster fire has a silver lining when people who deserve it get burned.

InsidiousWombat 1 hour ago | parent

now I kinda wanna shadow the usual SSH creds files with LLM read-only user, so it can rummage thru the repos all it wants but I need to do the push using my creds.

misnome 3 hours ago | parent

Has anyone managed to confirm the time that the backdoored version was released? None of my machines updated to it, I am wondering if it was saved by a combination of luck and

> This extension is not updated yet because new versions become eligible for automatic update 12 hours after they are published. It will become eligible in 2 hours.

helsinkiandrew 3 hours ago | parent

> Yesterday, Anthropic were compromised and Cursor extension used by tens of millions of developers for Claude access was delivering a remote access trojan via an SSH reverse backdoor

That's a bit hyperbolic: someone released a version of the Claude Code VS Code extension with a backdoor on the Cursor marketplace:

> a maliciously modified version of Anthropic’s Claude Code extension was made available in the Cursor VS Code extension Marketplace

https://cursor.com/blog/claude-code-extension-security-notic...

darkwi11ow 3 hours ago | parent

Nah it was Anthropic, see my comment at https://news.ycombinator.com/reply?id=50302513&goto=item%3Fi...

Cursor does a bad reporting branding OpenVSX as "Cursor Marketplace". What a joke the company had become under Elon. But also it might be related to Anthropic/SpaceX business ties, they try to minimize damage on Anthropic pre-IPO

swingboy 3 hours ago | parent

Wasn’t it called Cursor Marketplace pre-Elon?

darkwi11ow 3 hours ago | parent

Cursor always used OpenVSX for VSCode extensions. There is separate "Cursor Marketplace" (https://cursor.com/marketplace) but it installs "Cursor Plugins" which are exclusively Cursor feature not related to VSCode, and Anthropic had never released a "Cursor Plugin"

mirashii 1 hour ago | parent

Cursor didn’t always use Open VSX, it changed in late 2025. https://forum.cursor.com/t/extension-marketplace-changes-tra...

Also worth noting that it doesn’t use Open VSX directly but uses a cursor hosted mirror at https://marketplace.cursorapi.com/open-vsx-mirror

darkwi11ow 1 hour ago | parent

Thanks for correction!

square_usual 1 hour ago | parent

From "I suspect it was Anthropic" to "Nah it was anthropic", it's amazing how disinformation spreads... when even your source says:

> but it is unclear whether his account or another part of the publishing process was compromised.

God, people get so conspiratorial on HN when it comes to Ant

JeremyNT 1 hour ago | parent

Direct link to Binance assertions you mentioned [0]

The Binance post should probably be the root link for this topic not this blog post - IMO

[0] https://www.binance.com/en/square/post/10-30-2026-claude-cod...

qwrkll 54 minutes ago | parent

As the article says, version 2.1.313 was silently deleted from OpenVSX, Visual Studio Marketplace and Cursor.

There is more going on here. Cursor is covering for Anthropic because of the huge data center contract with SpaceX.

literallyroy 18 minutes ago | parent

No the version was skipped. 2.1.314 was published instead. Issue is with Cursor marketplace nothing else.

anon-3988 3 hours ago | parent

I have this realization recently that everyone that uses Claude Code or Codex have basically been running RCE code on a daily basis (me included). So much for "be careful about running curl | bash!". That puts it into perspective what does security and privacy really mean? For all I know, these CLIs could have been secretly scraping my entire directory. Who's checking?

staminade 3 hours ago | parent

This was a compromise of the extension. The same kind of supply-chain attack could happen to literally any extension, package or other piece of software you install. Not excusing Anthropic letting this happen, but it doesn't have any bearing on the security and privacy of using Claude Code or Codex. Yes, you need to be careful about what they do. The fact that you might still get pwned via some other vector is irrelevant.

minraws 3 hours ago | parent

Can't their millions of agent swarms detect a malicious supply chain vector, sure it can happen to any company but not the one people are literally handing over their entire companies too.

Anthropic holds the SLA/MSA agreements not this bad actors what happens to your data is unknown if these become frequent and accepted. Given how much data is piped to Claude code via these services/extensions.

Den_VR 3 hours ago | parent

There’s a reason codex and the like improved like they did. You can simply look. Or hear about it on podcasts.

snaking0776 3 hours ago | parent

In at least one case they were! https://cybernews.com/ai-news/grok-build-git-repository-uplo...

origini 3 hours ago | parent

Don't forget: To make LLM useful you give it EVERYTHING it needs to know to be useful and if you don't use a certain provider with proper legal status, this is just gone.

We probably transfered more code/codebases and company secrets to random endpoints than ever before.

Btw. you could setup a sandbox and limit access

raxxorraxor 3 hours ago | parent

Both is completely secure theoretically. You can read the output of the curl before you refetch and pipe it to bash. You can also look at the commands claude is executing.

You always do that, right? ...right?

deadbabe 2 hours ago | parent

No but we use MCP so we’re fine.

novafunc 2 hours ago | parent

I used to think the same, but apparently there's a way to differentiate between curling into bash and curling into a text file.

So you could be diligent and curl into a text file, see nothing is wrong, but then when you curl into bash, it runs something different.

wolttam 2 hours ago | parent

    curl > some_file
    bash some_file
(Also, how in the world would a server be able to tell where you’re piping the response?)

Edit: thanks for the replies, that makes perfect sense

foodevl 1 hour ago | parent

Timing. A megabyte of "sleep 10;" would be read from the server more slowly when piped to bash versus written to a file

vladvasiliu 2 hours ago | parent

I think the difference people were warned about is that the server can infer the client, so there would be a difference between reading it in your regular browser and curling. As the other commenter says, I'm not sure how the server would be able to tell what curl does with the response.

magnio 3 hours ago | parent

> Who's checking?

Yeah I sympathize with people saying software developers should not be called engineers too.

palata 2 hours ago | parent

I think that software engineering is very much engineering.

I just think that the level of malpractice in software engineering is a lot higher than in other engineering fields, for some reasons.

knottn 2 hours ago | parent

Maybe it’s easier to outsource.

jimbokun 58 minutes ago | parent

Because there’s no credentialing thus no fear of losing those hard earned credentials.

TheCapn 42 minutes ago | parent

I'm just going to copy-paste my own comment from a few weeks ago because I feel like it is needing to be said more and more recently

---

I have, off and on, for years written diatribes about how if people in our industry want to run around with the "Engineer" moniker at some point they should start acting like it. That means respecting all aspects of what it means to be an Engineer and holding public well-being paramount is part of that. Licensure is part of that. Accountability and Responsibility is part of that.

I'm usually downvoted. The move fast and break things group seems to be blind (or willfully ignorant) to the harm that software systems can carry on a person's life. I don't know if its fear of regulation, or self-serving interests or some sort of disdain for the idea that we need to slow down and be more accountable to the public or what. At times the people I've engaged with lament on how they're capable but would be barred for lack of formal education or some such and its a distraction from the overall point: we need to be doing better and if we can't self-regulate then at some point we're going to be forced to act in a way that probably cuffs us more than necessary.

And yes, I understand how Software doesn't exactly fit into the mold of other engineering disciplines cleanly. But I think the idea that if we're going to have systems that can ruin a person's life in a second for a bug or oversight we need to start considering that accountability for those releasing software to the public matters. We lament about the difficulty of holding corporations to account for their harm, but it would be far more difficult for a company's negligence to hurt people if those turning the knobs were held to a higher standard.

I think that reckoning is coming soon. AI is going to create "an event" that we can't ignore and we're going to be pointing fingers in a lot of directions asking "how" we could prevent this from happening again. I'd argue "the event" has already occurred a few times over but we're purposely ignoring the severity of it to keep a diseased economy running roughshod. There's parallels with many historic events forcing regulation and the path forward won't be clean and easy.

darkwi11ow 2 hours ago | parent

I only use agentic development tools in qemu VM that has no production access or host shared folders, and the only secrets there are development. I still have my Git ssh key there, but I never use ssh agent to load the keys. The worst that agentic tools can do to me, is to install keylogger and compromise my ssh key and password, but even then my deployment workflow includes creating release in Github, which is not possible via ssh key only. I was very lucky to avoid the hack yesterday, as I use Claude installed via OpenVSX, but even if I installed the compromised version, the damage would be minimal.

hangrybear666 2 hours ago | parent

Hell yeah that's the most sane and efficient personal dev sandboxing work flow I've heard and shows you know your stuff. Just basics but executed very well.

rietta 2 hours ago | parent

I am doing similar with Debian 13 images in QEMU. Only access is to code specifically SSH in. On some, I am taking it a step further and my SSH key is not present at all on the bot. I add it as a git remote from my host into the VM and push and pull from there and then push to GitHub myself. So the agent has no path to GitHub either.

darkwi11ow 2 hours ago | parent

Wow, great notion about using git remote to transfer source from the agent host. I already use ssh into VM to transfer the files like designs for sharing, so going to adopt your approach right now :)

rietta 1 hour ago | parent

Yup, I give them a custom entry in ~/.ssh/config like:

``` host claudebox hostname 192.168.122.105 user developer IdentityFile ~/.ssh/id_rsa ```

``` host codexbox hostname 192.168.122.106 user developer IdentityFile ~/.ssh/id_rsa ```

I drop only my public key inside the VM. Then I set up the ~/Projects folder with the code the bot is working on any any authorized samples.

Then in my local on my host clone of the repository, I add another remote like

``` git remote add codexbox ssh://codexbox/home/developer/Projects/hello-world ```

Then git push codexbox.

Then I just SSH in or use the vm gui and interact with the agent there. I like to keep it running in byobu so I can remote in more easily when I am on the laptop out and about.

AdrianCX 3 hours ago | parent

https://www.reuters.com/business/media-telecom/cursor-says-u...

> Cursor said the extension was not developed by Anthropic and the maliciously modified extension was live on the marketplace from about 2:27 a.m. PT to 1:35 p.m. PT on Thursday

So is this or isn't this from Anthropic and how did this happen?

iugtmkbdfil834 3 hours ago | parent

Isn't it fun when all the lines are blurred and it is hard to tell what belongs where?

darkwi11ow 3 hours ago | parent

It was likely Anthropic, see my comment in other thread: https://news.ycombinator.com/reply?id=50302513&goto=item%3Fi... . Cursor likely on purpose does bad reporting to minimize damage on Anthropic pre-IPO (as SpaceX and Anthropic have extensive business ties)

origini 3 hours ago | parent

I don't think Spacex cares at all about Anthropics IPO just because they rent out their compute.

Big companies are not just 'Company' they are a lot of small teams doing their own things. They need to coordinate with other people for public announcements etc. and security team is probably also looking at it.

stopsayingsorry 3 hours ago | parent

People at the top know that, once the music stops, the ball is over for everyone.

stingraycharles 2 hours ago | parent

Wasn’t Elon Musk shouting a few days ago that neoclouds are going to crash, the money dried up and that SpaceX was the last company with the opportunity to raise more money?

I think you’re giving Musk too much credit.

kirth_gersen 2 hours ago | parent

True, but there are other people working at the companies that probably own stock in both their own company and some of the others...if you believe that this is the future, you'd be a fool to buy non-AI tech stocks, right?

chrisgarand 1 hour ago | parent

Neoclouds aren't Anthropic, OpenAI, and SpaceX. People aren't going to re-value value SpaceX on CoreWeave's success.

SpaceX will be re-valued on Anthropic's, or OpenAI's success, he, and his people are smart enough to understand this.

alpha_squared 1 hour ago | parent

Didn't SpaceX partially admit they're a neocloud in their S-1?

extraextra 58 minutes ago | parent

He specifically said that lender money dried up for neocloud companies that don't have other sources of income

SpaceX obviously has multiple sources of income, not just data center rents

chrisgarand 5 minutes ago | parent

They do have their own segment that is considered neocloud (data centers for compute), but they're mostly/fully used up with their own, and Anthropic's compute.

When he was talking about neoclouds, he was talking about the smaller guys who are getting bullied by vendors (mainly Nvidia) to buy as much hardware as possible (more than they want to). They paid more, for more, and needed to take on more debt, to end up (currently anyways) being well below capacity.

Over the next few years, unless growth keeps up (and probably accelerates), they'll need to sell, or restructure.

The buildouts by Microsoft, Google, Meta, OpenAI, and Anthropic are currently safe. The neoclouds that they've signed contracts with, are safe, but based on reports, that's roughly 60% of current capacity (it varies by report, but they're all under 75%).

bix6 1 hour ago | parent

Somebody doesn’t want anybody to have a bigger IPO than them.

lkbm 1 hour ago | parent

The person at the top refers to Anthropic as "Misanthropic". It seems unlikely that they're also intentionally lying about this to protect Anthropic's interests.

Your conspiracy theory needs some work.

AdrianCX 3 hours ago | parent

OpenVSX has no extension signing, no verification, nothing...

So really, there's no way to say what was compromised and where.

This could have been avoided by having extensions signed by company doing them with their own keys and have them reviewed

WarmWash 1 hour ago | parent

It's annoying how fast people run to conspiracy.

jorisw 1 hour ago | parent

And pretend to know and understand the ties between big names

mrweasel 3 hours ago | parent

Obviously Anthropic didn't develop a malicious extension, but did they publish it? Did it sneak in, in a 3rd party library, or does someone have access to their marketplace account?

stingraycharles 2 hours ago | parent

For what it’s worth, at one point one of our employees windows machines got infected, and the moment he did $something with Wordpress it intercepted the HTTP post and injected malware in there.

So that’s how these things can go, the employee’s machine may have been infected which was then used to inject this.

cookiengineer 1 hour ago | parent

LGTM [1] sing

In all seriousness, there is nobody at Anthropic who can even give you that answer, because nobody there reads their pushed code anymore. Take a look at the previous Claude Code leaked codebases if you don't believe me, there is hundreds of files with 1000+ or more import statements at the top.

Any human would immediately tell you that it needs to be refactored from scratch. Their codebase also leaked that they're using review bots automatically instead of a human-in-the-loop review process.

[1] https://m.youtube.com/watch?v=3TNpOD6bov8

edit: downvoting me doesn't make it untrue, by the way. Check the leaked codebases, I dare you to provide evidence to the contrary.

tekawade 1 hour ago | parent

Anthropic only has an official extension for VS Code. Cursor is vs code fork and gave its own marketplace.

IIUC Anthropic does not publish extensions for Cursor. It’s basically, official Claude code extension “clone” not by Anthropic.

Ai summary in better words: The Recent Malicious Build (v2.1.313): A tampered version of this extension (version 2.1.313) was uploaded to the Cursor extension marketplace. This specific, malicious build was not developed or authorized by Anthropic. Attackers effectively hijacked or spoofed the extension's legitimate identity within the Cursor/Open-VSX system to bundle an unauthorized SSH backdoor into the real Anthropic code.

no-name-here 19 minutes ago | parent

> Anthropic only has an official extension for VS Code.

That likely seems incorrect as I see Claude Code listed on open-vsx with:

* An "Anthropic" "Verified publisher" badge

* igorkofman listed who seems to be an Anthropic employee

* 63M downloads

* Reviews going back >1 year

https://open-vsx.org/extension/Anthropic/claude-code

ddworken 21 minutes ago | parent

Dworken from Anthropic here, this did not involve a compromise of any Anthropic systems. A malicious actor used access to Cursor’s marketplace to publish a tampered extension targeting Cursor's users, we were not involved with building, publishing, or hosting this. The versions on our official channels including VS Code and OpenVSX are not affected and this only impacts Cursor users.

HexDecOctBin 3 hours ago | parent

> Claude Code for VS Code extension on the Cursor Marketplace

So Cursor is running its own extension repository? Or is this the official VS Code repository and the incident report just happens to focus on Cursor for some reason?

NewsaHackO 3 hours ago | parent

VS Code doesn't allow forks to use their marketplace, I think. At least with VSCodium, they don't. I think they even patch a workaround where you could download almost all extensions' .vsix files.

altbdoor 3 hours ago | parent

1. If only Cursor Marketplace version was compromised, how was it published in the first place?

2. If the Cursor Marketplace version was released from an "official Anthropic" account, whose to say OpenVSX and/or VSCode versions are not compromised?

The affected versions have been pulled down, so no one really knows. The way I see it, only Cursor has admitted to have been compromised.

stbenjam 3 hours ago | parent

We still don’t know exactly what happened, but I publish software to public registries, and supply chain attacks scare the hell out of me. They also frustrate me, because most of the defenses aren't automatic and often really hard to get right. We're really failing as an industry to do better here.

poelzi 3 hours ago | parent

This is why I started to move more and more into my tix.im environment. You can't trust anything anymore - I assume everything is compromised if not proven otherwise.

poelzi 3 hours ago | parent

I guess, this is why I'm building tix.im ...

jedisct1 3 hours ago | parent

Keep sending all your secrets and giving full control of your devices to Anthropic.

This is fine.

VoidWhisperer 3 hours ago | parent

My question here - does this effect those of us using the official vscode/vscode marketplace? It would seem to imply this was specific to cursor's marketplace but it would be good to know regardless

gcr 2 hours ago | parent

Kevin Beaumont says the extension for “VSCode and Cursor” was compromised: https://cyberplace.social/@GossiTheDog/117528831681803563

orlp 3 hours ago | parent

So if this happened to OpenAI it would've been instantly auto-updated everywhere? VS Code has an "auto update delay" which I have configured to a week, but I just found out that (https://code.visualstudio.com/updates/v1_123):

> Note: This delay does not apply to extensions from trusted publishers such as Microsoft, GitHub, and OpenAI. These extensions continue to update immediately.

You can't even configure which publishers you "trust"...

CoastalCoder 2 hours ago | parent

Does anyone know Microsoft's justification for that policy?

bikeshaving 2 hours ago | parent

Windows has a builtin keyboard shortcut to open LinkedIn. This is just how they do things.

masfuerte 51 minutes ago | parent

I thought that couldn't really be true. I was wrong.

https://www.theverge.com/2023/9/15/23874798/microsoft-window...

IshKebab 2 hours ago | parent

"Of course we don't make mistakes. There's no need to delay our updates."

dgellow 2 hours ago | parent

Wtf. That’s its own scandal

delis-thumbs-7e 1 hour ago | parent

I started experimenting with more traditional text editors since last spring and am happy to say, that I’m a happy user of Neovim now.

dcrazy 1 hour ago | parent

If it defaulted to a week then it actually would have helped mitigated the spread. But it defaults to 2 hours, so there was a 9 hour window during prime US working hours yesterday when machines would have been auto-updating to the compromised extension.

Though Anthropic is claiming that the compromised package was published solely to Cursor’s marketplace, not not Microsoft’s.

numbsafari 3 hours ago | parent

This puts an entirely new spin on Elon trolling Binance on Twitter.

paaloeye 2 hours ago | parent

It's karma I guess

efficax 3 hours ago | parent

either the registry is compromised or someone at anthropic got compromised (or did it on purpose to steal crypto). the line in the cursor disclosure about the extension not being developed by anthropic is more confusing than clarifying. amateur hour for these massive corps

xteam 3 hours ago | parent

♟

rvz 2 hours ago | parent

This is embarrassing to Anthropic given here that they lack basic security procedures to prevent this and they have gotten themselves hacked to push malware.

Claude Code was already malware, but with this attack you cannot trust the vendor either.

In the next 2 weeks, no one should download / install / update anything as I predict at least one developer's key for a GitHub, NPM, Crates.io or any other CI or login was leaked and the attacker will target those services to propagate their trojan to more victims.

yubblegum 2 hours ago | parent

The original Phorion report really should be up here. It even details what exactly happened. So they simply added a ssh key to the authorized keys.

https://phorion.io/blog/offical-claude-code-vsx-compromise/

stingraycharles 2 hours ago | parent

And try to launch sshd, right? Think of all the other things they could have done…

lesspassiveobse 2 hours ago | parent

Not only launch sshd. They set up a reverse tunnel connection.

anonymous908213 2 hours ago | parent

If it is true that Binance was compromised as a result of this, hats off to our new billionaire friend for one hell of a heist.

Aboutplants 2 hours ago | parent

Is that the rumor? Does the timing line up?

anonymous908213 2 hours ago | parent

It does. The compromised extension was published about 11 hours before Binance's coins went zoop, Binance blamed a compromised developer laptop, and OP pointed out that their hiring page explicitly notes developers will be using Cursor with Claude Code for "development efficiency".

Aboutplants 2 hours ago | parent

Incredible. Looking a bit more and more like this was the actual case. Wild stuff

nater5000 26 minutes ago | parent

>hats off to our new billionaire friend

As if this wasn't coordinated by a team directed by the government of North Korea.

paaloeye 2 hours ago | parent

Another reason for not using VS Code and derived and all their mess of extensions. I'm glad running Claude Code in Ghostty/Terminal is not affected.

jitbit 2 hours ago | parent

Oh god... this needs more attention

An official announcement from Anthropic would be nice!

stingraycharles 2 hours ago | parent

I’d expect nothing less than a post mortem on how this happened to be honest.

lxgr 2 hours ago | parent

Something very similar is true for ChatGPT on macOS. I was recently very surprised to learn that starting a "Work" conversation on my Mac would grant the agent session file system access which can later be used remotely, e.g. from a browser session logged into the same account on a different computer.

Given how many people likely share ChatGPT subscriptions, this seems highly problematic.

reilly3000 2 hours ago | parent

My tin foil hat says MSFT stands the most to gain my this. https://open-vsx.org/ is where the attack took place, and that power’s all of the VSCode fork’s extensions needs.

blondie9x 2 hours ago | parent

From https://doublepulsar.com/anthropic-hacked-to-deliver-remote-...

Notable customers who run Claude Code and Cursor on laptops include Binance, amongst thousands of others.

Did the Claude Code plugin hack cause the Binance theft? The timing seems like an incredible coincidence.

DEADF007 2 hours ago | parent

I don't care anymore, how are you supposed to defend yourself against attacks like this? Come and hack me.

anonymous908213 2 hours ago | parent

> how are you supposed to defend yourself against attacks like this?

You can try not installing malware like Claude Code or, if you absolutely must, doing it in a sandbox.

tripleee 1 hour ago | parent

I thoroughly sandbox agents to their own physical machine, and they don't have access to anything that would ruin me.

try-working 2 hours ago | parent

"Software is solved. Bugs are not yet solved"

paxy 2 hours ago | parent

Is there any proof of this or are we just upvoting garbage?

strix_varius 1 hour ago | parent

https://cursor.com/blog/claude-code-extension-security-notic...

paxy 1 hour ago | parent

I don't see "Anthropic hacked!" anywhere in that post. This extension was uploaded to the Cursor marketplace.

maayank 2 hours ago | parent

Have we just witnessed the greatest lateral movement in cybersecurity history? https://x.com/dinodaizovi/status/2116125553665458463?a=D1DiF...

rietta 2 hours ago | parent

Reading the report alone: "First, the payload makes sure ~/.ssh exists and appends an attacker-controlled Ed25519 public key to ~/.ssh/authorized_keys, setting permissions to 0700 on the directory and 0600 on the file."

A system where ~/.ssh/authorized_keys has not been modified might be a hint that this did not execute - the article does not mention self cleanup/reverting to previous status behavior by the malware. By default /var/log/auth.log is only of marginal value because outbound SSH connections are not logged by default.

kirth_gersen 2 hours ago | parent

This is why when I use AI, I still download from the browser and drag and drop the outputted files like a caveman. Sure, it's slower, but it keeps my mental model more up to date and has less security risks. I can even...like read the thing before I run it rather than giving a LLM access to my shell directly. Also anecdotally, it seems more token efficient for those who care about that.

gruez 2 hours ago | parent

That's not the actual hack though, it's with an extension. You could have gotten compromised this way through an extension for git or whatever.

_hmj 2 hours ago | parent

Development must occur in an isolated VM, with no access to the publishing workflow. CI operations must happen in a separate VM or on the host system after scanning all files. Thus, even if the development tools are compromised (like this case), the impact is limited.

Still, it’s hardly a surprise that best practices are rarely followed with any consistency.

villgax 2 hours ago | parent

What I dont understand is why the hell do these extensions & clis need to update every damn day. clearly there's no new models everyday, what the actual f.

meindnoch 1 hour ago | parent

Because we need velocity. If we don't have velocity, we die.

soundworlds 2 hours ago | parent

The descriptions around this are very confusing. Is this specifically the Cursor version, or the regular VS Code version too?

paaloeye 1 hour ago | parent

P(doom) crowd say Anthropic has not zero chance to destroy humanity. What it is, the VS Code Extension Marketplace, including Cursor's, must be bigger.

jacquesm 1 hour ago | parent

Anthropic is a weird company. On the one hand they have this messianic thing about their super intelligence, on the other hand it is incapable of keeping their own house secure. But you should trust it.

pier25 1 hour ago | parent

God only knows how many skeletons like this are in Bun now

Handy-Man 1 hour ago | parent

That's not official extension though? Misleading title

felixrieseberg 1 hour ago | parent

Felix from Anthropic here.

We’re working with Cursor on this incident, but it wasn’t a compromise of Anthropic’s systems or employee laptops. A malicious actor used access to Cursor’s marketplace to publish a tampered copy of the Claude Code extension, which we didn’t build or publish. The versions on our official channels are not affected and this only impacts Cursor users.

ashishb 1 hour ago | parent

The extensions does not need full access to the laptop.

When you are invited to someone's living room, you don't get to access their bedroom.

The idea that Claude should have full data access to the home directory is wrong. And as an industry leader, Claude has set a bad precedence.

hobo123 1 hour ago | parent

Probably a good idea to only run LLMs with a dedicated user account, or in a container.

ashishb 1 hour ago | parent

Dedicated user account does not work as eventually all your code and data will move under that.

I run it in an ephemeral container sandbox (https://github.com/ashishb/amazing-sandbox) which has access to the current working directory and it drastically limits the attack radius.

no-name-here 24 minutes ago | parent

For locally installed Code / Code-fork extensions, there is not any concept of permissions (at least on Windows or MacOS (+ the 3rd party code-server running on Linux)), correct?

fishfasell 1 hour ago | parent

I'm assuming there is no way to prevent this without Cursor improving their extension vetting? Seems like folks are confused in the comments here. To me, this is a 3rd party marketplace that lives outside of Anthropic's governance, is that correct?

ddworken 1 hour ago | parent

Dworken from Anthropic here, yes this is correct. This is a third-party marketplace that we are not involved in owning, maintaining, deploying, or reviewing.

junofan 32 minutes ago | parent

Is the extension not Anthropic.claude-code developed by Anthropic? Been a while since I used Cursor.

no-name-here 10 minutes ago | parent

> Cursor routes extension search and downloads through its own marketplace proxy (marketplace.cursorapi.com), not a direct passthrough to Open VSX.

https://cursor.com/help/customization/extensions

JeremyNT 1 hour ago | parent

If this isn't a damning indictment of Cursor, I don't know what is. Perhaps it will be the death knell.

What value is this VS fork actually adding given today's advanced harnesses? Surely whatever benefits it offers are not worth the risks going forward.

nikanj 1 hour ago | parent

I believe the value add was $60bn in just 4 years https://www.linkedin.com/posts/sytaylor_wild-cursor-just-sol...

lifeisloving 1 hour ago | parent

I dont know a single person who uses this tool (but im sure there are some) our annual subs recently ran out, I hadnt used mine in 6 months, we did not renew.

Elon did the typical boomer tech guy thing when they interact with any slightly impressive AI tool.. Lose their fkn mind and spend tons of money on it. He just took it to another level..

Its like those tech boomers that got obsessed with openclaw and instantly started spending 20k a month on a thing that read their calender outloud to them.

user43928 40 minutes ago | parent

Cursor made Grok Bot and is working on the Grok models.

I wouldn't say it's obviously unsuccessful.

jmull 19 minutes ago | parent

Musk is solidly gen-x.

(I realize it doesn't matter to those of you with a rather "lo-res" perspective on things. To put it in a nice way.)

sunaookami 1 hour ago | parent

>Perhaps it will be the death knell

People said the same thing about SolarWinds, Lenovo (Superfish), CrowdStrike... Nothing will happen.

airhangerf15 39 minutes ago | parent

I'm still surprised people use CrowdStrike. I guess there are no real alternatives. I know companies are getting CrowdStrike alerts for this very issue, but it still just seems like a MASSIVE attack surface.

Back when I was in DevOps, the Linux Falcon Sensor was an absolutely disaster. They recompiled it for EVERY kernel release of every supported distribution (they had never heard of DPMS apparently), the service ran as root, it UPDATED ITS OWN BINARIES as root! It broke nearly ever Linux design philosophy.

I know newer version use eBPF and don't have the stupid kernel lock-in issue, but I still don't trust it.

Aboutplants 1 hour ago | parent

Seeing as SpaceX owns Curser, I’m surprised there wasn’t a hack on SpaceX… Yet

gpm 35 minutes ago | parent

Who says there wasn't?

A lot of the most valuable SpaceX IP (at least to the big "advanced persistent threat" hackers) is probably related to military secrets, information to let you spy on/disable/control star shield/link, and so on. Not things we'd find out about as the general public.

numbsafari 32 minutes ago | parent

I mean, who says it wasn't an inside job...

https://www.cnbc.com/2026/10/30/binance-hack-elon-musk-tesla...

elevation 1 hour ago | parent

> We’re working with Cursor on this incident

Could be better to say "we're working with the Cursor team on this incident". Not your intent, but I initially understood that the Claude team was using Cursor-the-product (instead of Claude-the-product) to resolve the backdoors.

blactuary 1 hour ago | parent

Memphis will remember each and every one of you

ipsento606 1 hour ago | parent

The situation is confusing, so can I please confirm the following:

* "Cursor Editor" is a fork of VS Code

* The "Claude Code for VS Code" extension, v2.1.313, was compromised specifically on the Cursor Editor extension marketplace / distribution system

* The "Claude Code for VS Code" extension for regular VS Code on the official VS Code extension marketplace was not affected

Followup question: was a v2.1.313 also published on the official VS Code marketplace? If so, your statement is that that version was not compromised?

wky 1 hour ago | parent

Even more confusing is apparently Cursor Marketplace is OpenVSX + their own proxy to add extensions on top[0], so there are at least two possible cases:

1. The compromised version was present on OpenVSX itself, and Cursor Marketplace proxied to it

2. The compromised version was on Cursor's proxy, not OpenVSX itself

[0] https://cursor.com/help/customization/extensions

ddworken 1 hour ago | parent

Dworken from Anthropic here, that is correct: This only impacted the extension as it was hosted on the Cursor marketplace. It did not impact the official VS Code extension marketplace or OpenVSX. Users of Claude Code on VS Code are not impacted by this issue.

qwrkll 52 minutes ago | parent

Why was version 2.1.313 silently deleted from OpenVSX, Visual Studio Marketplace and Cursor then?

https://doublepulsar.com/anthropic-hacked-to-deliver-remote-...

perching_aix 51 minutes ago | parent

I'm guessing it was the easiest quick workaround available, but obv wait for official confirmation.

Reads like Cursor's extension marketplace got compromised, hence how the OpenVSX and MS marketplaces can be unaffected.

Handy-Man 49 minutes ago | parent

313 was never released lol https://github.com/anthropics/claude-code/releases

ddworken 48 minutes ago | parent

Dworken from Anthropic here, 2.1.313 was never published on OpenVSX, the VS Code marketplace, or on any of our official hosts. The malicious actor here had published a fake version of this extension on Cursor's marketplace. In order to disambiguate, we made sure our next update was 2.1.314.

skinfaxi 35 minutes ago | parent

Why was the npm version 2.1.313 yanked?

https://www.npmjs.com/package/@anthropic-ai/claude-code?acti...

ddworken 20 minutes ago | parent

Dworken from Anthropic here, 2.1.313 was never published on OpenVSX, the VS Code marketplace, or on any of our official hosts. The malicious actor here had published a fake version of this extension on Cursor's marketplace. In order to disambiguate, we made sure our next update was 2.1.314.

officeplant 27 minutes ago | parent

smooth sloperators, smooooooooth sloperattorrrrrssss

acedTrex 1 hour ago | parent

Thankfully coding is solved everyone

shahbaby 1 hour ago | parent

I think right now AI is helping the attackers more than it's helping the defenders.

That part is probably obvious.

But in the long term, I suspect this will get worse.

Attackers will still need to think critically to be a few steps ahead of the defenders.

But the defenders will increasingly outsource their thinking to AI as they are incentived if not outright forced to dumb themselves down into interchangeable cogs.

felixrieseberg 1 hour ago | parent

Felix from Anthropic here.

We’re working with Cursor on this incident, but it wasn’t a compromise of Anthropic’s systems or employee laptops. A malicious actor used access to Cursor’s marketplace to publish a tampered copy of the Claude Code extension, which we didn’t build or publish. The versions on our official channels are not affected and this only impacts Cursor users.

cryptonym 56 minutes ago | parent

> A malicious actor used access to Cursor’s marketplace

How did they get access to this?

Handy-Man 51 minutes ago | parent

Ask Cursor team?

ihuman 1 hour ago | parent

This is just the version of extension on the Cursor marketplace, not the one on the VS Code marketplace, right?

kiproping 55 minutes ago | parent

More details from Kevin Beaumont. "Anthropic got compromised. Their Claude Code extension on Visual Studio Code and Cursor has malware in it, which creates a remote access Trojan to desktops. " https://cyberplace.social/@GossiTheDog/117528831681803563

Glyptodon 48 minutes ago | parent

Normal VS code doesn't even use Cursor Marketplace, right? The way this is reported lacks clarity. Do people using plain CS Code even use the Cursor Marketplace? Or am I missing something?

rhedak 36 minutes ago | parent

Honestly with AI getting smarter it feels like these kind of attacks will only increase...

vanbashan 33 minutes ago | parent

Is it related to today binance event?

paxy 23 minutes ago | parent

So let me get this straight – Elon was trolling Binance on Twitter, when in fact it was his own company that got hacked and led to the theft?

Aboutplants 9 minutes ago | parent

Yup

ricky_risky 18 minutes ago | parent

not just anthropic, my product that used antigravity is also leaked and copied by google, these close ai company will undoubtably steal your code, file and data.

strongly suggest put your valuable work on local llm.

hemlock4593 9 minutes ago | parent

It's funny that's the point where people draw the line. But that basically every API based agent is doing RCE where commands are fetched from servers is perfectly fine.

hughw 3 minutes ago | parent

Idea: why don't all the various app stores and plugin repos use LLMs to review all submissions for security? Certainly in the human powered age that was too big a task to take on, but now it seems doable.