CVE-2020-5290: Ctfd Rctf

Medium severity, CVSS 6.5. EPSS: 0.8% chance of exploitation in the next 30 days.

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.

Affected products

• Ctfd Rctf: before 2.3 (fixed in 2.3)

Published 2020-04-01. Last modified 2026-06-17.