I can’t find any mention online of the `SystemTokenInformation` enum member outside of this article, even in this otherwise very comprehensive collection of documented and undocumented values: https://www.geoffchappell.com/studies/windows/km/ntoskrnl/ap...

Seems like SystemTokenInformation might be a very new addition, possibly even Windows 11 only?

I'm pretty sure it's just a small mistake in the article on the exact syscall used to query the token information.

Checked a kernel from November 2024 vs a current one and from I can tell, this used to be the actual mechanism the exploit worked:

  Thread #1 looping
    NtQueryInformationToken(TokenAccessInformation, InfoBuffer);
  
  Thread #2 looping
    Ptr = *(InfoBuffer + SidHashOffset);
    if (IsValidCanonicalKernelPtr(Ptr))
      done

Sorry, the article was fixed with the right class and syscall names; somehow, it slipped past review.