CVE-2026-9084 (GCVE-0-2026-9084)
Vulnerability from cvelistv5 – Published: 2026-05-20 14:22 – Updated: 2026-05-20 15:28
VLAI
EPSS
VEX
Title
MISP OIDC authentication bypass via automatic email-based account linking under insecure IdP configurations
Summary
MISP’s OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local account had no stored sub value. Under insecure or untrusted IdP configurations where email ownership is not enforced, an attacker with a valid OIDC token could assert a victim’s email address and authenticate as that user, leading to account takeover.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-20 15:28 UTC
CWE
- CWE-287 - Improper Authentication
Assigner
CIRCL
CNA
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/MISP/MISP/commit/71f5662c1b588… | patch |
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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