CVE-2026-82465 (GCVE-0-2026-82465)
Vulnerability from cvelistv5 – Published: 2026-08-29 16:35 – Updated: 2026-08-29 16:35
VLAI
EPSS
VEX
Title
pac4j-saml before 6.5.6 Session Destruction via Unsigned LogoutRequest
Summary
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.
Severity
5.3 (Medium)
CWE
- CWE-345 - Insufficient Verification of Data Authenticity
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/pac4j/pac4j/commit/2270c3ff70e… | patch |
| https://www.pac4j.org/blog/security-advisory-pac4… | vendor-advisory |
| https://github.com/pac4j/pac4j/blob/pac4j-parent-… | technical-description |
| https://github.com/pac4j/pac4j | product |
| https://www.vulncheck.com/advisories/pac4j-saml-b… | third-party-advisory |
Impacted products
Date Public
2026-08-24 00:00
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}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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