Note that the shell might have its own builtin time implementation, which may behave differently than
/usr/bin/time, hence the absolute path.
It can be used to break out from restricted environments by spawning an interactive system shell.
It runs with the SUID bit set and may be exploited to access the file system, escalate or maintain access with elevated privileges working as a SUID backdoor. If it is used to run
sh -p, omit the
-p argument on systems like Debian (<= Stretch) that allow the default
sh shell to run with SUID privileges.
sudo sh -c 'cp $(which time) .; chmod +s ./time' ./time /bin/sh -p
It runs in privileged context and may be used to access the file system, escalate or maintain access with elevated privileges if enabled on
sudo /usr/bin/time /bin/sh