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seanheelanon I used o3 to find a remote zeroday in the Linux SMB implementation

I honestly hadn’t anticipated someone would think I hadn’t bothered to verify the vulnerability is real ;)

Since you’re interested: the bug is real but it is, I think, hard to exploit in real world scenarios. I haven’t tried. The timing you need to achieve is quite precise and tight. There are better bugs in ksmbd from an exploitation point of view. All of that is a bit of a “luxury problem” from the PoV of assessing progress in LLM capabilities at finding vulnerabilities though. We can worry about ranking bugs based on convenience for RCE once we can reliably find them at all.

seanheelanon I used o3 to find a remote zeroday in the Linux SMB implementation

Hi, author here. Yes, I built a PoC. Yes, it triggered a KASAN report/crash.

seanheelanon I used o3 to find a remote zeroday in the Linux SMB implementation

I realised I didn't mention it in the article, so in case you're curious it cost about $116 to run the 100k token version 100 times.

seanheelanon I used o3 to find a remote zeroday in the Linux SMB implementation

It's certainly not the first vulnerability found with an LLM =) Perhaps I should have been more clear though.

What the post says is "Understanding the vulnerability requires reasoning about concurrent connections to the server, and how they may share various objects in specific circumstances. o3 was able to comprehend this and spot a location where a particular object that is not referenced counted is freed while still being accessible by another thread. As far as I'm aware, this is the first public discussion of a vulnerability of that nature being found by a LLM."

The point I was trying to make is that, as far as I'm aware, this is the first public documentation of an LLM figuring out that sort of bug (non-trivial amount of code, bug results from concurrent access to shared resources). To me at least, this is an interesting marker of LLM progress.