Yet another Hacker News

CVE-2026-98432: Linux TCP Use-After-Free Risk and Patch Validation

38 points cobychapple 3 hours ago 27 comments

rvz 2 hours ago | parent

This one is quite serious and the type of vulnerability is once again, a C style memory corruption and a race condition combined; leading to an RCE.

At this point, we seriously need to discuss whether if the major projects still written in C such as Linux, Chromium and even git can even handle the stream of now near infinite bugs being discovered with AI.

Attackers are already rapidly finding and building exploits for those vulnerabilities the moment they are discovered with abliterated frontier-level models.

These sort of vulnerabilities are far to common in those projects and in the future, it will be extremely unsafe for even experts to continue using C or C++ in any way.

worthless-trash 2 hours ago | parent

Leading 'maybe' to an RCE, i imagine you need to groom the heap first, unless there is something i'm missing.

Edit: also thanks for using RCE correctly, it seems to be any kind of code execution these days is considered "RCE".. boo.

MithrilTuxedo 2 hours ago | parent

I bet there's a half-life to bugs though. Bugs might be infinite over the lifespan of a project, but the rate that they are produced goes down with our ability to detect them.

A lot are being found _now_ in projects written in C because the backlog of bugs to find is mostly written in C. We haven't yet gotten to the point when we're detecting most bugs before they're released, but we will.

Things won't get worse for too long. If we haven't already surpassed it, we're approaching the point of being able to do static analysis and ensure the mathematical correctness of the most complex C programs ever written so far.

I don't use C or C++, but look how much safer it is to use C or C++ these days.

spauldo 2 hours ago | parent

Unless someone vibecodes a new OS and convinces everyone to use it, we're stuck with what we got. Reaching feature parity with Linux and then debugging it to the point where it'd be usable is a gargantuan undertaking.

schainks 56 minutes ago | parent

Don't tempt DHH. Omarchy works WAY better than expected, and made my 2017 MBP very usable again.

perching_aix 1 hour ago | parent

You severely underestimate humanity's goalpost moving capabilities.

The state of cope:

- models are still not intelligent, they're just like, uhh, really good semantic fuzzers! so you can just put them in the loop, they'll fuzz your code, and all is good :)

- the number of bugs is "finite", so - esp with agentic help - we'll just catch up and all will be good :)

Annoyingly, the cope frontier is kinda right about both of these, so the joke shall go on. The only real counter to it would be to bring up that this finiteness claim only really applies to a frozen set of security boundaries and attack surfaces, but they'll probably just raise this being "an academic tier concern" and just tell you to ""fuzz"" more.

So ironically, it looks like these practices are rescued once again, and the bare minimum stays winning. It also starts being moved to the territory of the magic box, but I guess nobody cares about that anymore. Local AI will just get really good too, fully competitive and self hostable even. Any day now.

From the horse's mouth, in case you were suspecting these descriptions to be in bad faith: https://www.youtube.com/watch?v=NnV_cWeoo5Q

drdexebtjl 1 hour ago | parent

> Attackers are already rapidly finding and building exploits for those vulnerabilities the moment they are discovered with abliterated frontier-level models.

Are they? Distributions are rating this at a lower severity presumably because it can’t be easily exploited.

majorchord 2 hours ago | parent

Thankfully the vast majority of servers are not creating MPTCP listeners by default (that I'm aware of).

Not sure why the article doesn't mention it, but you can specifically check for MPTCP listeners using `ss -M`.

drum55 2 hours ago | parent

https://go.dev/doc/go1.24

> ListenConfig now uses MPTCP by default on systems where it is supported (currently on Linux only).

This seems to imply basically any golang server built since February 2025 is going to be at least attempting to use it.

aarjaneiro 38 minutes ago | parent

Yeah seems you're right...

Luckily though, ListenConfig lets you override this https://cs.opensource.google/go/go/+/refs/tags/go1.27.3:src/...

raggi 1 hour ago | parent

mptpcp usage is not a prerequisite

superkuh 2 hours ago | parent

Would dropping these specialized ipv4 syn packets with extra header size beyond 20 bytes (as indicated by options value >5) with the firewall be low enough in the order of things to mitigate the attack? Like, iptables -A INPUT -p tcp --syn -m u32 --u32 "0>>24&0xF=6:15" -j DROP ?

ReDress 2 hours ago | parent

I fail to understand / find the gist of this article.

Article describes the technical aspects of the bug, how it got handled by different vendors...AI position on it...

But, one would always ask themselves, why did the author write this article? That part hasn't been clear to me even after going through much of the article.

vikramkr 57 minutes ago | parent

I believe the author of this article is in fact most likely a large matrix multiplication and that it is possible that no human even initiated the computation of said multiplication directly. I assume it's not hard to set up some monitor for new CVEs to try and slop out an article as quickly as possible to get as revenue

drum55 2 hours ago | parent

This is a good portion just slop, another 9000 word article that could have been a couple of paragraphs. More text doesn't mean better.

gnabgib 1 hour ago | parent

There's other coverage, this just has most of the comments now

Ubuntu (34 points, 16 hours ago, 3 comments) https://news.ycombinator.com/item?id=50287647

CVE.org (2 points, 7 hours ago) https://news.ycombinator.com/item?id=50295879

GoogleGroups (slight tangent) Go programs enable MPTCP by default, exposing them to Linux CVE-2026-98432 (9 points, 3 hours ago, 4 comments) https://news.ycombinator.com/item?id=50298526

walrus01 38 minutes ago | parent

It would have been about 50x less annoying if whoever was driving the LLM had simply told it to make a clickable top of page index/headers in markdown and divide it into sections and subsections by logical topic.

aussieguy1234 1 hour ago | parent

Given these types of security bugs that are being found left and right, I reckon there's going to be an uptick in hiring of software engineers to fix them.

SkyPuncher 1 hour ago | parent

I strongly doubt that. The fixes for most of these are trivial to the point it’s almost automated.

Incipient 39 minutes ago | parent

I suspect a lot of organisations are already on automated AI detect-patch-redeploy loops for a lot of these types of issues.

cadamsdotcom 1 hour ago | parent

Whoever failed to edit this CVE description down owes us all a bunch of our time back

Everyone using LLMs needs to stop shipping their first draft.

walrus01 40 minutes ago | parent

"Haven't had enough yet of very junior engineers pasting wall-of-text from chatgpt at you in Slack? Come on down to the CVE announcement emporium, where we have a special treat for you today..."

Rapzid 1 hour ago | parent

  Cee Vee Eee week ends
  The buffers overflowing
  Cancel all your plans

schainks 58 minutes ago | parent

  Debian patched it up
  Red Hat says "Fix is deferred"
  Pull the network plug

walrus01 50 minutes ago | parent

The overlaid HTML popup on that page for "Try The World's First Agentic AI Hacker." tool is cancerous and annoying. This should really be a link to a more reputable link for the CVE in question.

It doesn't appear until you've read the page for maybe 10-15 seconds, so if you're not seeing it, just wait.

It even managed to get past ublock origin, since there's no specific rule for it yet.

snvzz 39 minutes ago | parent

There's no end to bugs like these in Linux. Millions of Lines of Code can easily hide many, many of these. Code that runs in supervisor mode.

None of this can ever affect seL4[0] nor a system built on it, due to its architecture.

0. https://sel4.systems/