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Keycloak client updates silently disable offline token revocation

Priority LOW 19CWE-862Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-862.

Summary

Red Hat build of Keycloak 26.6 contains a flaw in the OIDC Dynamic Client Registration component. A bug in response serialization (CWE-862) omits the backchannel logout offline token revocation setting, so a standard client update silently disables it. As a result, offline tokens may remain valid after a user session is terminated via backchannel logout. A remote user with low privileges can trigger this without user interaction.

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

Description from the CNA

A flaw was found in the OIDC Dynamic Client Registration (DCR) component of Keycloak. A bug in the response serialization causes the backchannel logout offline token revocation setting to be omitted from responses. When a client performs a standard update, this missing information causes the setting to be silently disabled. As a result, offline tokens may remain valid even after a user session is terminated via backchannel logout.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00196 9th percentileScored 2026-11-07
Fix Fixed Red Hat: 2 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
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 Single Sign-On 7——Not affectedCNA
  • 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 Single Sign-On 7 VendorRed Hat Affected — Fixed in — Not affected CNA

CPE names CNA · 2

CPEVersionsRoleVendor
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:26.6::el9 Versions 26.6 — ·Red Hat
  • cpe:/a:redhat:red_hat_single_sign_on:7 Versions 7 — ·Red Hat

Remediation

Red Hat build of Keycloak 26.6 is fixed in 26.6.8-2 and 26.6-24, as described in RHSA-2026:95761 and RHSA-2026:95762. Red Hat build of Keycloak 26.6.8 and Red Hat Single Sign-On 7 are listed as not affected.

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

Red Hat 2 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-2026:95761 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

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
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. 2026-10-08 Threatist record created from CVE-2026-107623
  2. 2026-10-08 Alias added: GHSA-qxj8-968q-qm7w
  3. 2026-10-08 CISA SSVC decision points changed
  4. 2026-10-09 Affected versions changed · Red Hat
  5. 2026-10-09 CVSS score added · Red Hat
  6. 2026-11-06 Affected versions changed · CNA
  7. 2026-11-06 1 new reference · CNA
  8. 2026-11-06 Fix available: RHSA-2026:95761 · Red Hat
  9. 2026-11-06 Fix available: Red Hat build of Keycloak 26.6.8 · Red Hat
  10. 2026-11-06 Fix available: rhbk/[email protected], rhbk/[email protected], rhbk/[email protected] · CNA
  11. 2026-11-06 1 new reference · CNA
  12. 2026-11-06 Fix available: RHSA-2026:95762 · Red Hat
  13. 2026-11-06 Fix available: Red Hat build of Keycloak 26.6 · Red Hat

References

  • 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