Everything for the CTF will be on the domain Unless otherwise noted, all flags will have be in the following format: RSXC{<flag>}

Standard rules apply:
  • Do not attack any other ports or paths than specifed in challenges
  • Do not attack our infrastructure
  • Do not attack other players
If you have any questions or there are any issues. Please contact us on our discord channel designated for River Security Xmas Challenge (RSXC).


River Security has a prize pool for what we deem to be the best write-ups. Only writeups sent in before 27.12.2021 will be eligeable for prizes. Please do not publish or share your own writeups publically before this date. We ask that each contestant only submit writeups once, by email to rsxc @

Prize pool

  1. Burp License
  2. 4k Apple TV
  3. Onyx Studio 4 speaker