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TI-2026-85536 Aliases CVE-2026-97174GHSA-42wm-mqj8-5cwr

Keycloak CIBA injection lets attackers receive tokens for other users

Priority LOW 32CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
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 26.6 is affected. The CIBA endpoint fails to validate the sub parameter (CWE-20), so an injected value is stored as an extra request parameter and overwrites the legitimate subject during token issuance. A remote attacker with low privileges can authenticate as themselves and receive security tokens belonging to a victim user, which leads to unauthorized account access.

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

Description from the CNA

A flaw was found in the Client-Initiated Backchannel Authentication (CIBA) implementation of Keycloak. The CIBA endpoint fails to properly validate the sub parameter, allowing it to be stored as an additional request parameter. During the token issuance process, this injected value overwrites the legitimate subject identifier. This allows an attacker to authenticate as themselves but receive security tokens belonging to a different victim user, leading to unauthorized account access.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00367 30th 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
Total

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, per RHSA-2026:95762 and RHSA-2026:95761. 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: Important. 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. 2026-11-05 Threatist record created from CVE-2026-97174
  2. 2026-11-05 Alias added: GHSA-42wm-mqj8-5cwr
  3. 2026-11-05 Affected versions changed · Red Hat
  4. 2026-11-05 CVSS score added · Red Hat
  5. 2026-11-05 CISA SSVC decision points changed
  6. 2026-11-05 Priority changed: MEDIUM → LOW
  7. 2026-11-06 Affected versions changed · CNA
  8. 2026-11-06 1 new reference · CNA
  9. 2026-11-06 Fix available: RHSA-2026:95761 · Red Hat
  10. 2026-11-06 Fix available: Red Hat build of Keycloak 26.6.8 · Red Hat
  11. 2026-11-06 Fix available: rhbk/[email protected], rhbk/[email protected], rhbk/[email protected] · CNA
  12. 2026-11-06 1 new reference · CNA
  13. 2026-11-06 Fix available: RHSA-2026:95762 · Red Hat
  14. 2026-11-06 Fix available: Red Hat build of Keycloak 26.6 · Red Hat

References

Advisory 2

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