High · published May 22, 2026
RT is an open source, enterprise-grade issue and ticket tracking system. Versions 5.0.9 and prior in addition to 6.0.0 through 6.0.2 contain an authentication bypass vulnerability in RT installations that use LDAP/AD for user authentication. Under certain LDAP server configurations, an attacker may be able to authenticate as any LDAP-backed RT user without supplying valid credentials. This issue has been fixed in versions 5.0.10 and 6.0.3. If developers are unable to upgrade immediately, they can temporarily work around this issue by reviewing their LDAP server's authentication policy to ensure it rejects unauthenticated bind attempts. Upgrading RT remains the recommended fix.