In RedpwnCTF before version 2.3, there is a session fixation vulnerability in exploitable through the `#token=$ssid` hash when making a request to the `/verify` endpoint. An attacker team could potentially steal flags by, for example, exploiting a stored XSS payload in a CTF challenge so that victim teams who solve the challenge are unknowingly (and against their will) signed into the attacker team's account. Then, the attacker can gain points / value off the backs of the victims. This is patched in version 2.3.
Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.
| Link | Tags |
|---|---|
| https://github.com/redpwn/rctf/security/advisories/GHSA-p5fh-2vhw-fvpq | third party advisory exploit |
| https://github.com/redpwn/rctf/issues/147 | third party advisory exploit |