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I think you have figured out where I am getting at.

As long as processes can rewrite their own cmdline and process names, you have a conceptual problem that you can only solve with kernel hooks (or eBPF modules).

The persistence techniques in the article were easy to follow, but all that alias mess, path mess, and glibc dependent mess makes everything that you execute untrustable.

The cli commands that were posted in the sibling comments all rely on procfs and the faked names :) so they won't actually detect it if a process rewrote its cmdline or has an in memory .so file that was changed and loaded from somewhere else (e.g. via LD_PRELOAD).

LD_PRELOAD is quite easy to detect, though nobody seems to be aware of its effects. And that is a 10 years known vulnerability and part of every standard audit by now. None of the posted answers even check for the environment files in procfs.

We're not talking about a bug in glibc here, because it is intended and documented behavior. If it was a bug, it would be much much worse.

edit: I wanted to add that the POSIX and Linux way of doing things would require a specific user for each program in order to be successful. But this is a prime example of what can go wrong when a user (and its groups) is used for multiple things. Any process that is running as the same (non-root) user can modify those procfs files. And I think that's a HUGE problem.






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