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TI-2026-85504 Aliases CVE-2026-107602GHSA-pv56-v62v-px29

Infinite loop in Keycloak SAML parser enables denial of service

Priority LOW 34CWE-835Published · 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-835.

Summary

The SAML 1.1 XML parser in Keycloak, an open-source identity and access management solution, is affected in Red Hat build of Keycloak 26.4 and 26.6. When the parser meets unexpected elements in a security token's key information section, its processing thread enters an infinite loop (CWE-835). An unauthenticated remote attacker can send crafted requests to drive CPU usage to 100% and cause a total denial of service that requires a server restart to resolve.

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

Description from the CNA

A flaw was found in the SAML 1.1 XML parsing logic of Keycloak, an open-source identity and access management solution. The issue occurs when the parser encounters unexpected elements within a security token's key information section, causing the processing thread to enter an infinite loop. An unauthenticated remote attacker could exploit this by sending specially crafted requests, leading to 100% CPU usage and a total denial of service that requires a server restart to resolve.

Why it matters now

EPSS 0.00734 54th 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 26.6—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 26.4 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 26.6 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 · 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 build of Keycloak 26.4 is fixed in 26.4.17-2, 26.4-29 and 26.4-30, and 26.6 is fixed in 26.6.8-2 and 26.6-24. Red Hat advisories RHSA-2026:95759, RHSA-2026:95760, RHSA-2026:95761 and RHSA-2026:95762 provide these fixes. Red Hat build of Keycloak 26.4.17, 26.6.8 and Red Hat Single Sign-On 7 are 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-2026-107602
  2. 2026-11-05 Alias added: GHSA-pv56-v62v-px29
  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 EPSS moved to the 50th–90th percentile
  16. 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