Summary

This is basically GHSA-88j4-pcx8-q4q but instead of changing passwords, when enabling authentication.

PoC

• Open Uptime Kuma with authentication disabled
• Enable authentication using another window
• Access the platform using the previously logged-in window
• Note that access (read-write) remains despite the enabled authentication
• Expected behaviour:
  • After enabling authentication, all previously connected sessions should be invalidated, requiring users to log in.
• Actual behaviour:
  • The system retains sessions and never logs out users unless explicitly done by clicking logout or refreshing the page.

Impact

See GHSA-g9v2-wqcj-j99g and GHSA-88j4-pcx8-q4q

TBH this is quite a niche edge case, so I don't know if this even warrants a security report.