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TI-2026-85533 Aliases CVE-2026-92857GHSA-xw5c-j6m6-2hxj

Keycloak client registration mapper lets attackers forge token claims

Priority LOW 35CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

Red Hat build of Keycloak 26.4 and 26.6 are affected. The Dynamic Client Registration feature does not validate protocol mapper configuration (CWE-20), so a user holding an initial access token can map their own profile details onto the sub and aud claims. The attacker can register a malicious application that issues signed tokens making them appear as another user, which allows impersonation or access to services that rely on these tokens.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

Keycloak provides a Dynamic Client Registration feature that allows users with specific tokens to register their own applications. A flaw in how Keycloak validates these registration requests allows an attacker to create a malicious application that forges identity information. By mapping their own user profile details to protected fields like the user ID (sub) or intended audience (aud), an attacker can generate signed security tokens that make them appear to be a different user. This could allow an attacker to impersonate other users or gain unauthorized access to services that rely on these tokens for identity verification.

Why it matters now

EPSS 0.00361 30th percentileScored 2026-11-07
Fix Fixed Red Hat: 4 advisories

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
Red HatRed Hat build of Keycloak 26.4—26.4.17-2Patch availableCNA
Red HatRed Hat build of Keycloak 26.4—26.4-29Patch availableCNA
Red HatRed Hat build of Keycloak 26.4—26.4-30Patch availableCNA
Red HatRed Hat build of Keycloak 26.4.17——Not affectedCNA
Red HatRed Hat build of Keycloak 26.4.17——Not affectedCNA
Red HatRed Hat build of Keycloak 26.4.17——Not affectedCNA
Red HatRed Hat build of Keycloak 26.6—26.6.8-2Patch availableCNA
Red HatRed Hat build of Keycloak 26.6—26.6-24Patch availableCNA
Red HatRed Hat build of Keycloak 26.6—26.6-24Patch availableCNA
Red HatRed Hat build of Keycloak 26.6.8——Not affectedCNA
Red HatRed Hat build of Keycloak 26.6.8——Not affectedCNA
Red HatRed Hat build of Keycloak 26.6.8——Not affectedCNA
Red HatRed Hat Single Sign-On 7——Not affectedCNA
  • Red Hat build of Keycloak 26.4 VendorRed Hat Affected — Fixed in 26.4.17-2 Patch available CNA
  • Red Hat build of Keycloak 26.4 VendorRed Hat Affected — Fixed in 26.4-29 Patch available CNA
  • Red Hat build of Keycloak 26.4 VendorRed Hat Affected — Fixed in 26.4-30 Patch available CNA
  • Red Hat build of Keycloak 26.4.17 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat build of Keycloak 26.4.17 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat build of Keycloak 26.4.17 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat build of Keycloak 26.6 VendorRed Hat Affected — Fixed in 26.6.8-2 Patch available CNA
  • Red Hat build of Keycloak 26.6 VendorRed Hat Affected — Fixed in 26.6-24 Patch available CNA
  • Red Hat build of Keycloak 26.6 VendorRed Hat Affected — Fixed in 26.6-24 Patch available CNA
  • Red Hat build of Keycloak 26.6.8 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat build of Keycloak 26.6.8 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat build of Keycloak 26.6.8 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat Single Sign-On 7 VendorRed Hat Affected — Fixed in — Not affected CNA

CPE names CNA · 3

CPEVersionsRoleVendor
cpe:/a:redhat:build_keycloak:26.4::el926.4—Red Hat
cpe:/a:redhat:build_keycloak:26.6::el926.6—Red Hat
cpe:/a:redhat:red_hat_single_sign_on:77—Red Hat
  • cpe:/a:redhat:build_keycloak:26.4::el9 Versions 26.4 — ·Red Hat
  • cpe:/a:redhat:build_keycloak:26.6::el9 Versions 26.6 — ·Red Hat
  • cpe:/a:redhat:red_hat_single_sign_on:7 Versions 7 — ·Red Hat

Remediation

Red Hat fixes this in Red Hat build of Keycloak 26.4 versions 26.4.17-2, 26.4-29 and 26.4-30, and in 26.6 versions 26.6.8-2 and 26.6-24, through advisories RHSA-2026:95759, RHSA-2026:95760, RHSA-2026:95761 and RHSA-2026:95762. Red Hat Single Sign-On 7 is not affected.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Red Hat 4 advisories

  • RHSA-2026:95762 Released 2026-11-06 · Red Hat rating Important
    Red Hat build of Keycloak 26.6.8 Images Security Update
    • Red Hat build of Keycloak 26.6 rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator
  • RHSA-2026:95760 Released 2026-11-06 · Red Hat rating Important
    Red Hat build of Keycloak 26.4.17 Images Security Update
    • Red Hat build of Keycloak 26.4 rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator
  • RHSA-2026:95761 Released 2026-11-06 · Red Hat rating Important
    Red Hat build of Keycloak 26.6.8 Security Update
    • Red Hat build of Keycloak 26.6.8
Show 1 more Red Hat advisories
  • RHSA-2026:95759 Released 2026-11-06 · Red Hat rating Important
    Red Hat build of Keycloak 26.4.17 Security Update
    • Red Hat build of Keycloak 26.4.17

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat build of Keycloak 26.4Fixed RHSA-2026:95760
Red Hat build of Keycloak 26.4.17Fixed RHSA-2026:95759
Red Hat build of Keycloak 26.6Fixed RHSA-2026:95762
Red Hat build of Keycloak 26.6.8Fixed RHSA-2026:95761
Not affected: 1 product
  • Red Hat Single Sign-On 7

Timeline

  1. 2026-11-05 Threatist record created from CVE-2026-92857
  2. 2026-11-05 Alias added: GHSA-xw5c-j6m6-2hxj
  3. 2026-11-05 Affected versions changed · Red Hat
  4. 2026-11-05 CVSS score added · Red Hat
  5. 2026-11-06 Fix available: [email protected], [email protected], [email protected] · CNA
  6. 2026-11-06 2 new references · CNA
  7. 2026-11-06 Fix available: RHSA-2026:95761 · Red Hat
  8. 2026-11-06 Fix available: Red Hat build of Keycloak 26.6.8 · Red Hat
  9. 2026-11-06 Fix available: rhbk/[email protected], rhbk/[email protected], rhbk/[email protected] +3 · CNA
  10. 2026-11-06 2 new references · CNA
  11. 2026-11-06 Fix available: RHSA-2026:95760 · Red Hat
  12. 2026-11-06 Fix available: RHSA-2026:95762 · Red Hat
  13. 2026-11-06 Fix available: RHSA-2026:95759 · Red Hat
  14. 2026-11-06 Fix available: Red Hat build of Keycloak 26.4, Red Hat build of Keycloak 26.4.17, Red Hat build of Keycloak 26.6 · Red Hat
  15. 2026-11-07 Priority changed: MEDIUM → LOW

References

Advisory 4

Other 2

  • TI-2019-15875 Protection mechanism failure in Jenkins Pipeline: Groovy Plugin KEVCVSS 3.1CRITICAL 9.9
  • TI-2019-15874 Protection mechanism failure in Jenkins Script Security Plugin KEVCVSS 3.1CRITICAL 9.9
  • TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-05363 Code injection in Elastic Kibana KEVCVSS 3.1CRITICAL 10.0
  • TI-2019-03949 Out-of-bounds write in ESXi and Horizon DaaS KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-16080 A code execution vulnerability exists in the Stapler web framework used by Jenkins 2.153… KEVCVSS 3.1CRITICAL 9.8
See all 7412 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences