This exploit works by spoofing a demon agent registration and checkins to open a TCP socket on the teamserver and read/write data from it. This allows attackers to leak origin IPs of teamservers and much more.

Target: https://github.com/HavocFramework/Havoc
Full analysis: https://blog.chebuya.com/posts/server-side-request-forgery-on-havoc-c2/ 

usage: exploit.py [-h] -t TARGET -i IP -p PORT [-A USER_AGENT] [-H HOSTNAME] [-u USERNAME] [-d DOMAIN_NAME]
                  [-n PROCESS_NAME] [-ip INTERNAL_IP]

options:
  -h, --help            show this help message and exit
  -t TARGET, --target TARGET
                        The listener target in URL format
  -i IP, --ip IP        The IP to open the socket with
  -p PORT, --port PORT  The port to open the socket with
  -A USER_AGENT, --user-agent USER_AGENT
                        The User Agent for the spoofed agent
  -H HOSTNAME, --hostname HOSTNAME
                        The hostname for the spoofed agent
  -u USERNAME, --username USERNAME
                        The username for the spoofed agent
  -d DOMAIN_NAME, --domain-name DOMAIN_NAME
                        The domain name for the spoofed agent
  -n PROCESS_NAME, --process-name PROCESS_NAME
                        The process name for the spoofed agent
  -ip INTERNAL_IP, --internal-ip INTERNAL_IP
                        The internal ip for the spoofed agent

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Havoc C2 0.7 Teamserver SSRF exploit