Vikunja before 2.7.1 contains an information disclosure vulnerability that allows authenticated users to determine…

Vikunja before 2.7.1 contains an information disclosure vulnerability that allows authenticated users to determine whether private teams exist by calling the team member self-removal endpoint. Attackers can send DELETE requests to /teams/{id}/members/{own username} for arbitrary team ids and use the distinguishable responses to learn if a team exists, is SSO-managed, or has a single member.