CVE-2026-82465

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-29 17:17

Updated : 2026-09-10 19:54

NVD link : CVE-2026-82465

Mitre link : CVE-2026-82465

CVE.ORG link : CVE-2026-82465

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

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