This can be run with elevated privileges to change permissions and then read, write, or execute a file.
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 chmod) .; chmod +s ./chmod' LFILE=file_to_change ./chmod 0777 $LFILE
It runs in privileged context and may be used to access the file system, escalate or maintain access with elevated privileges if enabled on
LFILE=file_to_change sudo chmod 0777 $LFILE