As far as I know, pkexec doesn't validate arguments, so it might not be ideal if you are worried about people trying to trick it.
On Sat, Dec 15, 2018 at 6:15 AM JungHwan Kang <ultrac...@gmail.com> wrote: > Sometimes, I use a sudo command with -s options for keeping > environment variables for users account(sudoer). I also know -s option > runs the shell specified by the SHELL environment variable. But the > SHELL environment variable can be manipulated by other users having > the same privilege. > > So, I think an adversary is able to abuse the changing SHELL > environment variable for privilege escalation like a video below. (I > assume the adversary owned the permission for executing a shell on a > remote) > > https://youtu.be/JSQjIm7377o (unlisted state) > > I know it is uncertain when the sudo is executed with -s option by sudoer. > > Anyway, I have thought of the solutions to the issue below. > - using a pkexec of a Policy kit, > - disable a ptrace function via kernel.yama.ptrace_scope, CAP_SYS_PTRACE. > > Could you give some advice and comments? > > Thx. > >
