The Atlassian Questions For Confluence app for Confluence Server and Data Center creates a Confluence user account in the confluence-users group with the username disabledsystemuser and a hardcoded password. A remote, unauthenticated attacker with knowledge of the hardcoded password could exploit this to log into Confluence and access all content accessible to users in the confluence-users group. This user account is created when installing versions 2.7.34, 2.7.35, and 3.0.2 of the app.
https://jira.atlassian.com/browse/CONFSERVER-79483
https://confluence.atlassian.com/doc/confluence-security-advisory-2022-07-20-1142446709.html