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TI-2026-85503 Aliases CVE-2026-107123GHSA-85r4-9fq8-q8x4

Keycloak SAML XML parsing allows CPU exhaustion denial of service

Priority MEDIUM 40CWE-400Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-400.

Summary

Red Hat build of Keycloak 26.6 is affected. The SAML XML processing component does not validate excessively long dateTime and duration values, so the XML parser consumes excessive CPU time (CWE-400). An unauthenticated remote attacker can send crafted SAML requests, causing high CPU use and a denial of service for all users.

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

Description from the CNA

A flaw was found in the SAML XML processing component of Keycloak, an open-source identity and access management solution. The issue occurs when the server parses XML documents containing excessively long dateTime or duration values. Because these strings are not properly validated before processing, the XML parser consumes excessive CPU time. An unauthenticated remote attacker can exploit this by sending specially crafted SAML requests to the server, leading to high CPU utilization and a denial of service for all users.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00686 52nd percentileScored 2026-11-07
Fix Fixed Red Hat: 2 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
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 Single Sign-On 7 is 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-2026-107123
  2. 2026-11-05 Alias added: GHSA-85r4-9fq8-q8x4
  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
  15. 2026-11-07 EPSS moved to the 50th–90th percentile
  16. 2026-11-08 Priority changed: LOW → MEDIUM

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 7413 →

Sources

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