Abusing Symbolic Links Like It's 1999

An anonymous reader writes with this snippet from James Forshaw's recent post at Google's Project Zero, which begins For the past couple of years I've been researching Windows elevation of privilege attacks. This might be escaping sandboxing or gaining system privileges. One of the techniques I've used multiple times is abusing the symbolic link facilities of the Windows operating system to redirect privileged code to create files or registry keys to escape the restrictive execution context. Symbolic links in themselves are not vulnerabilities, instead they're useful primitives for exploiting different classes of vulnerabilities such as resource planting or time-of-check time-of-use. Click through that link to see examples of this abuse in action, but also information about how the underlying risks have been (or can be) mitigated.

Comments

Re:we can fix this

[Calydor]

The end of your post combined with your signature is comedy gold, mate.

Re: MS is still 20 years behind. This will remain

[Anonymous Coward]

Why have paid QA when your customers have proven over and over again that they'll still buy your software no matter how buggy it is? Thompson isn't that bright, and got his job just because of his race, but he isn't stupid.

As the old saying goes...

[turbidostato]

On proper time Windows has added symlinks, a (somehow) worthwhile command line, non-graphic environment, the ability to remotely manage, declarative-based configuration management...

It's only they are reinventing all these things on their own, forgetting about how did they came to be and, of course, not caring about the way those facilities have been used and abused in the past.

I think it was Henry Spencer the one that said "Those who do not understand Unix are condemned to reinvent it, poorly."