On: Environment Variables Considered Harmful for Your ...

[geocar]

Using a setuid helper (even if it's called sudo) is still starting a program as root.

[icebraining → geocar]

Not necessarily; sudo on Fedora has CAP_SETUID instead of the setuid bit, so it doesn't actually run as root.

http://fedoraproject.org/wiki/Features/RemoveSETUID

[ptx → icebraining]

But CAP_SETUID, unless I'm confusing it with something else, can be used to set the UID to 0 and thereby gain all the same privileges as if the program had been started as root, can't it? Presumably it has some advantage that I'm not getting – does it have to be combined with e.g. SELinux to be useful?