CVE-2026-9087 (GCVE-0-2026-9087)

Vulnerability from cvelistv5 – Published: 2026-05-20 16:13 – Updated: 2026-05-21 14:02
VLAI?
Title
Keycloak: cross-session email verification proof not bound to upstream identity in first-broker-login
Summary
A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.
Severity ?
6.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-9087 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2480172 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat Build of Keycloak     cpe:/a:redhat:build_keycloak:
 Create a notification for this product.
Date Public ?
2026-05-20 14:53
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

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.



Detection rules are retrieved from Rulezet.