pac4j-core before 6.5.6 contains an open redirect vulnerability in DefaultLogoutLogic.perform() that accepts backslash-prefixed logout redirect targets matching logoutUrlPattern. Attackers can craft logout links with backslash-prefixed external hosts that browsers normalize into network-path references, redirecting victims to attacker-controlled sites after logout.

pac4j-core before 6.5.6 contains an authentication bypass vulnerability in CheckProfileTypeAuthorizer that reverses the profile type validation logic. Attackers can authenticate through a weaker client and access resources requiring a stronger profile type by satisfying generic profile checks.