Tip: Install a Chromium flavor browser (Chromite) separate from the main browser.
Disable Javascript and hardware accelerated video decoder (commonly exploited) from the flags page and enable reader mode to fix broken JS-dependent websites when browsing blogs and random sites on your personal devices, else dedicate a tablet.
Thanks for testing, we currently only tested it on Pixel 10, but there are a few people on our repo creating PR to support other devices, you can take a look here https://github.com/NebuSec/CyberMeowfia
It's not so widely used and it's not explained in the first couple screenfuls of TFA (which by itself is weirdly structured, taking entire paragraphs to explain when it was introduced, when it was discovered, etc. before even explaining what it actually is).
Of course the title was chosen when the article was first published on a site dedicated to security, where probably everyone knows it. This suggests that insisting on unmodified titles when republishing in HN is a poor rule.
Has anyone in infosec ever seen the term "use after free" before LLMs? Or is this basically an acronym claude invented? I say this because I see claude use this term all the time like its common knowledge but in 15+ years in tech never seen it myself. I've seen all kinds of terms used to describe memory errors: memory corruption, heap corruption, stack corruption, whatever, just never this acronym.
everyone look at this guy, he's that much smarter and more expert than me, how could i have missed something so basic. i hope to aspire to your level some day.
There is an interesting episode of This American Life about how everyone, everyone, has weird gaps in their knowledge that eventually get filled in sometimes fun or humiliating ways. You have these too.
You only defended the initial attack, and went after the defense. It suggests you're not disinterested or participating with intent to further the conversation
Please don't be snarky or cross into putdowns or personal attack. We're all in (let's call it) the unlucky 10,000 about something. About most things actually.
if you have spend any amount of time in low level c vulnerabilities you will have heard about it, it is a very common time on the low level/cybersec space.
Yes, it was a common attack vector in binary exploitation. Heap based attack vector like use after free, double free, heap overflows, and others are pretty neat. They force you to learn a lot about how malloc works.
There is a lot of cool work that went into making memory allocation work well; the different arenas, fast bins, chunk headers, etc. are super cool.
This is and has been a common term in any systems programming concept for decades. You can, for example, search CVEs and easily find some from over 15 years ago: https://www.cve.org/CVERecord?id=CVE-2010-1119
It was even enumerated in the first pass of CWE as CWE-416 in 2006.
> This is the same shape as many other life-cycle bugs [...]
Claude-ism detected. According to it an object does not have a type or definition, apparently, but rather a shape (or at least it reaches for that word before more technically-accurate ones). Problems are not of a similar class or type, but of the same shape. Functions are not defined by their signatures but by their shape. Who talks like this and how did it make its way into the training data so pervasively?
>Google has rewarded us $92,337 in kernelCTF
I'm all ears now
Seems low considering the wide impact, but maybe the only thing corporations throw big money at is remote exploits?
That's a huge amount of money for a vulnerability.
Tested on three Android devices (version 9, 13, 16) with different Firefox versions under 150 (had to modify for older).
Two boot looped, I had to enter recovery and the other just powered off [0].
The demo modifies the wallpaper on supported Pixel devices.
[0] IonStack https://rootme.nebusec.ai
____
Tip: Install a Chromium flavor browser (Chromite) separate from the main browser.
Disable Javascript and hardware accelerated video decoder (commonly exploited) from the flags page and enable reader mode to fix broken JS-dependent websites when browsing blogs and random sites on your personal devices, else dedicate a tablet.
fwiw, the firefox vulnerability seems to be CVE-2026-10702 (type confusion in the ionmonkey jit compiler): https://www.sentinelone.com/vulnerability-database/cve-2026-...
Thanks for testing, we currently only tested it on Pixel 10, but there are a few people on our repo creating PR to support other devices, you can take a look here https://github.com/NebuSec/CyberMeowfia
Forgot to include "LPE" (local...) in the title so most of us can get back to weekending.
Since this enables container escape, sounds like this might still impact quite a lot of us?
A lot of us rely on Linux containers' being escape-proof?
I would have hoped that only a few of us are so misinformed as to do that.
I guess, if you thought Docker/etc. was a security boundary
they also found a type confusion in firefox/ionmonkey, so you can go from random website to pwned very quickly.
Daaaaamn: "GhostLock was introduced in Linux 2.6.39 and fixed in Linux 7.1."
A what?
Use after free?
Thanks! I've put that in the toptext now.
I'm glad someone else asked. :)
It's not so widely used and it's not explained in the first couple screenfuls of TFA (which by itself is weirdly structured, taking entire paragraphs to explain when it was introduced, when it was discovered, etc. before even explaining what it actually is).
Of course the title was chosen when the article was first published on a site dedicated to security, where probably everyone knows it. This suggests that insisting on unmodified titles when republishing in HN is a poor rule.
Not that everyone should know it but it's definitely widely used. A Google search for "stack UAF" also turns it up.
Has anyone in infosec ever seen the term "use after free" before LLMs? Or is this basically an acronym claude invented? I say this because I see claude use this term all the time like its common knowledge but in 15+ years in tech never seen it myself. I've seen all kinds of terms used to describe memory errors: memory corruption, heap corruption, stack corruption, whatever, just never this acronym.
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everyone look at this guy, he's that much smarter and more expert than me, how could i have missed something so basic. i hope to aspire to your level some day.
I do too, at some point I'm going to retire, and I hope you'll be looking down on people ignoring the twenty years of your career with disdain too!
Have fun with that.
Nah, I just find your clownish attempts at status games to be pathetic.
There is an interesting episode of This American Life about how everyone, everyone, has weird gaps in their knowledge that eventually get filled in sometimes fun or humiliating ways. You have these too.
Wow, what is that episode? I haven't listened to TAL in probably more than a decade but I'd have a go at that one
I can see that you're old and that I'm older, but I fail to see the justification for being snarky about that.
~ https://news.ycombinator.com/newsguidelines.html
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And a wrong justifies a wrong?
These are the times we make.
You only defended the initial attack, and went after the defense. It suggests you're not disinterested or participating with intent to further the conversation
Please don't be snarky or cross into putdowns or personal attack. We're all in (let's call it) the unlucky 10,000 about something. About most things actually.
https://news.ycombinator.com/newsguidelines.html
It has been a known bug class for quite some time.
if you have spend any amount of time in low level c vulnerabilities you will have heard about it, it is a very common time on the low level/cybersec space.
yes, it’s a very common term in infosec. I haven’t heard the “UAF” acronym before though
Yes, it was a common attack vector in binary exploitation. Heap based attack vector like use after free, double free, heap overflows, and others are pretty neat. They force you to learn a lot about how malloc works.
There is a lot of cool work that went into making memory allocation work well; the different arenas, fast bins, chunk headers, etc. are super cool.
This is and has been a common term in any systems programming concept for decades. You can, for example, search CVEs and easily find some from over 15 years ago: https://www.cve.org/CVERecord?id=CVE-2010-1119
It was even enumerated in the first pass of CWE as CWE-416 in 2006.
You have somehow lived in a strange bubble.
2025: https://redis.io/blog/security-advisory-cve-2025-49844/ 2023: https://seclists.org/oss-sec/2023/q2/133 2022: https://www.zerodayinitiative.com/advisories/ZDI-22-1690/ 2014: https://ftp.openbsd.org/pub/OpenBSD/patches/5.4/common/008_o...
It's an issue as old as time, or thereabouts.
I haven't really seen it as an acronym "UAF", but I can't recall the first time I heard "use after free". It was probably in the previous century.
The idea that Claude came up with it is ridiculous.
> This is the same shape as many other life-cycle bugs [...]
Claude-ism detected. According to it an object does not have a type or definition, apparently, but rather a shape (or at least it reaches for that word before more technically-accurate ones). Problems are not of a similar class or type, but of the same shape. Functions are not defined by their signatures but by their shape. Who talks like this and how did it make its way into the training data so pervasively?