CVE-2026-9084 (GCVE-0-2026-9084)

Vulnerability from cvelistv5 – Published: 2026-05-20 14:22 – Updated: 2026-05-20 15:28
VLAI?
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 ?
6 (Medium)
CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-287 - Improper Authentication
Assigner
References
Impacted products
Vendor Product Version
misp misp Affected: 2.5.0 , ≤ 2.5.37 (semver)
Create a notification for this product.
Credits
Ali Ganiyev Luciano Righetti
Show details on NVD website
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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

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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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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