Description
pac4j-saml before 6.5.6 does not require signature validation of SAML LogoutRequest messages in SAML2LogoutValidator.validateLogoutRequest(). When an IdP sends no SessionIndex, a session can be destroyed based solely on the NameID, allowing an unauthenticated attacker to submit an unsigned LogoutRequest with a guessed identifier (e.g., an email address used as NameID) to terminate a victim's SAML session.
Metrics
CVSS 3.1 5.3/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LWeakness enumeration
Affected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| pac4j | pac4j | < 6.5.6 |
References
- https://github.com/pac4j/pac4j
- https://github.com/pac4j/pac4j/blob/pac4j-parent-6.5.5/pac4j-saml/src/main/java/org/pac4j/saml/logout/impl/SAML2LogoutValidator.java
- https://github.com/pac4j/pac4j/commit/2270c3ff70e93cc43831e75702acd5135531237e
- https://www.pac4j.org/blog/security-advisory-pac4j-core-oidc-saml.html
- https://www.vulncheck.com/advisories/pac4j-saml-before-6.5.6-session-destruction-via-unsigned-logoutrequest
Timeline
- Published
- Aug 29, 2026
- Last modified
- Sep 10, 2026
- NVD status
- Awaiting Analysis