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Re:A buffer overflow in the XNU kernel by bartvk on Thursday June 20, 2024 @03:44PM (#40742512)
If you're still running the affected kernel, what are the possible consequences?

Also, this has been public for months:

- February 17, 2024: I posted the hash of TURPENTINE.c to X on Feb 17, 2024.

- May 13, 2024: macOS Sonoma 14.5 (23F79) shipped with xnu-10063.121.3, the first public release containing a fix.

Re:A buffer overflow in the XNU kernel by axoltl on Thursday June 20, 2024 @04:27PM (#40742988)
The syscalls involved are in a lot of sandboxes, so worst (or best, depending on your point of view) case scenario it's a pretty universal privesc. There's a lot of steps to get there though. I'm not super familiar with the mbuf subsystem specifically but I'm going to guess mbufs are in their own allocator zone. That means you're guaranteed to overwrite an adjacent m_hdr structure. Those contains pointers that form a linked list and at first glance I don't see linked list hardening or zone checks in the MBUF macros. One could envision being able to turn this bug into a kASLR leak as well as a kernel r/w primitive and while that isn't the silver bullet it used to be on XNU (because of a whole host of hardening Apple put in) it's still pretty powerful.
Re:A buffer overflow in the XNU kernel by TheDong on Thursday June 20, 2024 @11:49PM (#40745975)
> Also, this has been public for months:

Posting the hash to twitter as a proof that "something" exists reveals no actual information, so it's not considered making the exploit "public" in any meaningful way.

From the blog's timeline, it's been visible in code diffs since ~April, but only called out as a CVE since 10 days ago, so I'd consider this one hot off the presses.

Re:A buffer overflow in the XNU kernel by throwaway71271 on Thursday June 20, 2024 @03:56PM (#40742644)
I can't wait for gpt5 to be finetuned on all CVEs and their fixes so that you can just give it the linux source and it spits out exploits.

It will be absolute chaos.

Like when you can just send one icmp packet with `+++ath0` and just disconnect someone's modem, or open people's cdroms randomly at night haha.

Re:A buffer overflow in the XNU kernel by chad1n on Thursday June 20, 2024 @04:16PM (#40742872)
There is a bigger chance that a toddler smashing a keyboard finds a bug than gpt5. LLMs can't understand intent, so they literally work like `grep` with little to no understanding of the context, so most of the time it will false flag good code.

There are already a lot of tools already to find bugs, like fuzzers, but I am sure that LLMs won't be one of them.

Re:A buffer overflow in the XNU kernel by exe34 on Thursday June 20, 2024 @04:41PM (#40743134)
they don't need to understand intent, they just need to find exploits. they don't even need to do it by reading code alone - give them a vm running the code and let them throw excrement at it until something sticks!
Re:A buffer overflow in the XNU kernel by barkingcat on Thursday June 20, 2024 @04:53PM (#40743245)
Llm powered / guided fuzzer would be pretty cool though.
Re:A buffer overflow in the XNU kernel by zX41ZdbW on Thursday June 20, 2024 @05:08PM (#40743395)
Re:A buffer overflow in the XNU kernel by lpapez on Thursday June 20, 2024 @04:08PM (#40742782)
Writing an exploit is usually much more difficult than patching the underlying bug.

Half of the work in fixing a bug report is getting a reproducible example. Nay, more than half.

If there was a magic AI which could generate exploits, I'd imagine there would be an equally magic AI patching the holes right out.

Re:A buffer overflow in the XNU kernel by vlovich123 on Thursday June 20, 2024 @04:16PM (#40742876)
Maybe but keep in mind that there’s often a substantial lag in practice between a fixed vulnerability and its deployment into production.

That said, I’m quite skeptical there’s any AI’s on the horizon that can autogenerate exploits from CVEs.

Re:A buffer overflow in the XNU kernel by saagarjha on Thursday June 20, 2024 @03:57PM (#40742658)
It’s definitely nowhere near capable of doing that.
Re:A buffer overflow in the XNU kernel by favorited on Thursday June 20, 2024 @04:06PM (#40742766)
Is "with a sufficiently smart LLM" the new "with a sufficiently smart compiler?"
Re:A buffer overflow in the XNU kernel by st_goliath on Thursday June 20, 2024 @04:19PM (#40742907)
"imagine feeding this into an LLM/ChatGPT" is the new "imagine a Beowulf cluster of these"
Re:A buffer overflow in the XNU kernel by cozzyd on Thursday June 20, 2024 @09:14PM (#40745206)
grendellm?
Re:A buffer overflow in the XNU kernel by speed_spread on Thursday June 20, 2024 @04:17PM (#40742883)
GPT-5, maybe not. But somebody somewhere is building something that can do that. And if they can't do it _now_ they have a plan that tells them what's missing. TLDR; it's coming, soon.
Re:A buffer overflow in the XNU kernel by axoltl on Thursday June 20, 2024 @04:29PM (#40743009)
Writing exploits is a bit of an art-form. Current incarnations of GPT have trouble writing code at a level more advanced than a junior developer.
Re:A buffer overflow in the XNU kernel by TylerE on Thursday June 20, 2024 @04:25PM (#40742964)
and lots of people are spending lots of time and money on AI Coding Assitants... which is more or less the knowledge base you need.

If they could use that structural training to answer queries like "Is there any code path where some_dangerous_func() is called without it's return value being checked"...

Re:A buffer overflow in the XNU kernel by axoltl on Thursday June 20, 2024 @04:36PM (#40743089)
You can do this today by querying the AST output by a compiler. Regardless, the parent comment was talking about exploits, not vulnerabilities/bugs. Vulns are a dime-a-dozen compared to even PoC exploits let alone shippable exploits.
Re:A buffer overflow in the XNU kernel by TylerE on Thursday June 20, 2024 @05:03PM (#40743341)
Ok, so add "and generate a C program to exploit it" to the prompt.
Re:A buffer overflow in the XNU kernel by axoltl on Thursday June 20, 2024 @05:25PM (#40743571)
You're either being sarcastic or wildly underestimating how hard it is to write an exploit. I haven't written about exploit dev publicly for a _long_ time, but I invite you to read https://fail0verflow.com/blog/2014/hubcap-chromecast-root-pt... for what I consider to be a pretty trivial exploit of a very "squishy" (industry term) target.

XNU isn't the hardest target to pop but it is far from the easiest.

Re:A buffer overflow in the XNU kernel by poincaredisk on Friday June 21, 2024 @01:20AM (#40746401)
There's nobody more confident in the world, than HN poster wiring about a topic they have no experience with.

There is a huge gap (in the binary exploitation world) between identifying a problematic code pattern and having a workable bug (a reproduction), and even larger one between a reproducible crash and a working exploit (because we're not in the 90s anymore and complier/hardware mitigations are literally always enabled). Current LLMs can cross neither gap, and are not even close to bridging the second one.

Re:A buffer overflow in the XNU kernel by brcmthrowaway on Thursday June 20, 2024 @04:15PM (#40742862)
Have you used GPT-5?
Re:A buffer overflow in the XNU kernel by JSDevOps on Thursday June 20, 2024 @04:25PM (#40742965)
If you aren’t using GPT-6a then you are years behind.
Re:A buffer overflow in the XNU kernel by vips7L on Thursday June 20, 2024 @05:55PM (#40743855)
GPT-69 is already far ahead of 6a.
Re:A buffer overflow in the XNU kernel by JSDevOps on Thursday June 20, 2024 @06:10PM (#40743982)
Been using 73 for months now.
Re:A buffer overflow in the XNU kernel by exe34 on Thursday June 20, 2024 @04:42PM (#40743143)
you need to wake up at 4am and have a cold shower!
Re:A buffer overflow in the XNU kernel by JSDevOps on Thursday June 20, 2024 @05:02PM (#40743330)
12 before 12, 12 cold showers before 12 allowing GPT-7 to take care of my daily needs.
Re:A buffer overflow in the XNU kernel by sillywalk on Thursday June 20, 2024 @05:00PM (#40743307)
Apparently GPT-4 has some capacity to conduct exploits this by "reading" CVE reports. I don't know if it can autonomously create exploits though:

GPT-4 can exploit vulnerabilities by reading CVEs (theregister.com) 81 points by ignoramous 60 days ago | hide | past | favorite | 29 comments

https://news.ycombinator.com/item?id=40101846

which links to a Register Article[0], which links to a paper[1]:

"In this work, we show that LLM agents can autonomously exploit one-day vulnerabilities in real-world systems. To show this, we collected a dataset of 15 one-day vulnerabilities that include ones categorized as critical severity in the CVE description. When given the CVE description, GPT-4 is capable of exploiting 87% of these vulnerabilities compared to 0% for every other model we test (GPT-3.5, open-source LLMs) and open-source vulnerability scanners (ZAP and Metasploit). Fortunately, our GPT-4 agent requires the CVE description for high performance: without the description, GPT-4 can exploit only 7% of the vulnerabilities."[1]

[0] https://www.theregister.com/2024/04/17/gpt4_can_exploit_real...

[1] https://arxiv.org/pdf/2404.08144

Re:A buffer overflow in the XNU kernel by saagarjha on Thursday June 20, 2024 @06:49PM (#40744314)
Yes, that sounds about right. LLMs aren’t quite good enough to find novel bugs and exploit them like a human would.
Re:A buffer overflow in the XNU kernel by tedunangst on Thursday June 20, 2024 @07:09PM (#40744484)
Yeah, that works for web vulns where the vuln description is practically the exploit anyway. I could write a perl script that parses out variable names and writes sql injections for it.
Re:A buffer overflow in the XNU kernel by poincaredisk on Friday June 21, 2024 @01:17AM (#40746380)
For comparison, in the native world program is considered vulnerable when someone finds arbitrary write primitive (even without leak), use after free, and even double free. There is a huge gap between these and actually having a working RCE exploit. Most CVEs in this space are given without a working exploit ever written.
Re:A buffer overflow in the XNU kernel by jiveturkey on Thursday June 20, 2024 @04:33PM (#40743039)
the real win will be when it can also generate the codename for the exploit. FATEFATAL
Re:A buffer overflow in the XNU kernel by mschuster91 on Friday June 21, 2024 @03:45AM (#40747141)
> Like when you can just send one icmp packet with `+++ath0` and just disconnect someone's modem

Oh, I remember the "XDCC SEND KEYLOGGER 0 0 0" exploit from IRC era ~2010... dumbass middleboxes would yeet anyone whose packets crossed them.

Re:A buffer overflow in the XNU kernel by lgdskhglsa on Thursday June 20, 2024 @05:40PM (#40743708)
In case people missed it, the name of the exploit is a blink 182 song released around the time it was discovered.
Re:A buffer overflow in the XNU kernel by jprx on Thursday June 20, 2024 @05:46PM (#40743772)
You get it!!
Re:A buffer overflow in the XNU kernel by lgdskhglsa on Friday June 21, 2024 @04:07PM (#40753276)
It's my favorite song of the album :)
Re:A buffer overflow in the XNU kernel by 0757630110 on Saturday June 22, 2024 @10:44PM (#40764320)
So...