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TI-2025-10460 Aliases CVE-2025-11419GHSA-q8hq-4h99-fj7x

Keycloak: keycloak tls client-initiated renegotiation denial of service

Priority MEDIUM 40CWE-770Published · 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, GitHub and Red Hat. Impact type from CWE-770.

Summary

A flaw was found in Keycloak. This vulnerability allows an unauthenticated remote attacker to cause a denial of service (DoS) by repeatedly initiating TLS 1.2 client-initiated renegotiation requests to exhaust server CPU resources, making the service unavailable.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00718 54th percentileScored 2026-11-07
Fix Fixed keycloak: 26.0.16, 26.2.10, 26.4.1org.keycloak:keycloak-quarkus-dist (Maven): 26.0.16, 26.2.10, 26.4.1Red Hat: 4 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
—keycloakbefore 26.0.16; 26.2.0 to before 26.2.10; 26.4.0 to before 26.4.126.0.16, 26.2.10, 26.4.1Patch availableCNA
Red HatRed Hat build of Keycloak 26.0—26.0.16-2Patch availableCNA
Red HatRed Hat build of Keycloak 26.0—26.0-20Patch availableCNA
Red HatRed Hat build of Keycloak 26.0—26.0-21Patch availableCNA
Red HatRed Hat build of Keycloak 26.0.16——Not affectedCNA
Red HatRed Hat build of Keycloak 26.2—26.2.10-2Patch availableCNA
Red HatRed Hat build of Keycloak 26.2—26.2-11Patch availableCNA
Red HatRed Hat build of Keycloak 26.2—26.2-11Patch availableCNA
Red HatRed Hat build of Keycloak 26.2.10——Not affectedCNA
—org.keycloak:keycloak-quarkus-dist (Maven)before 26.0.1626.0.16Patch availableGHSA-q8hq-4h99-fj7x
—org.keycloak:keycloak-quarkus-dist (Maven)26.1.0 to before 26.2.1026.2.10Patch availableGHSA-q8hq-4h99-fj7x
—org.keycloak:keycloak-quarkus-dist (Maven)26.3.0 to before 26.4.126.4.1Patch availableGHSA-q8hq-4h99-fj7x
  • keycloak Vendor— Affected before 26.0.16; 26.2.0 to before 26.2.10; 26.4.0 to before 26.4.1 Fixed in 26.0.16, 26.2.10, 26.4.1 Patch available CNA
  • Red Hat build of Keycloak 26.0 VendorRed Hat Affected — Fixed in 26.0.16-2 Patch available CNA
  • Red Hat build of Keycloak 26.0 VendorRed Hat Affected — Fixed in 26.0-20 Patch available CNA
  • Red Hat build of Keycloak 26.0 VendorRed Hat Affected — Fixed in 26.0-21 Patch available CNA
  • Red Hat build of Keycloak 26.0.16 VendorRed Hat Affected — Fixed in — Not affected CNA
  • Red Hat build of Keycloak 26.2 VendorRed Hat Affected — Fixed in 26.2.10-2 Patch available CNA
  • Red Hat build of Keycloak 26.2 VendorRed Hat Affected — Fixed in 26.2-11 Patch available CNA
  • Red Hat build of Keycloak 26.2 VendorRed Hat Affected — Fixed in 26.2-11 Patch available CNA
  • Red Hat build of Keycloak 26.2.10 VendorRed Hat Affected — Fixed in — Not affected CNA
  • org.keycloak:keycloak-quarkus-dist (Maven) Vendor— Affected before 26.0.16 Fixed in 26.0.16 Patch available GHSA-q8hq-4h99-fj7x
  • org.keycloak:keycloak-quarkus-dist (Maven) Vendor— Affected 26.1.0 to before 26.2.10 Fixed in 26.2.10 Patch available GHSA-q8hq-4h99-fj7x
  • org.keycloak:keycloak-quarkus-dist (Maven) Vendor— Affected 26.3.0 to before 26.4.1 Fixed in 26.4.1 Patch available GHSA-q8hq-4h99-fj7x

CPE names CNA · 3

CPEVersionsRoleVendor
cpe:/a:redhat:build_keycloak:26.0::el926.0—Red Hat
cpe:/a:redhat:build_keycloak:26.026.0—Red Hat
cpe:/a:redhat:build_keycloak:26.2::el926.2—Red Hat
  • cpe:/a:redhat:build_keycloak:26.0::el9 Versions 26.0 — ·Red Hat
  • cpe:/a:redhat:build_keycloak:26.0 Versions 26.0 — ·Red Hat
  • cpe:/a:redhat:build_keycloak:26.2::el9 Versions 26.2 — ·Red Hat

Remediation

  • Fix · CNA keycloak Fixed in 26.0.16, 26.2.10, 26.4.1
  • Fix · GHSA-q8hq-4h99-fj7x org.keycloak:keycloak-quarkus-dist (Maven) Fixed in 26.0.16 Advisory →
  • Fix · GHSA-q8hq-4h99-fj7x org.keycloak:keycloak-quarkus-dist (Maven) Fixed in 26.2.10 Advisory →
  • Fix · GHSA-q8hq-4h99-fj7x org.keycloak:keycloak-quarkus-dist (Maven) Fixed in 26.4.1 Advisory →

Red Hat 4 advisories

  • RHSA-2025:18890 Released 2025-10-21 · Red Hat rating Important
    Red Hat build of Keycloak 26.2.10 Security Update
    • Red Hat build of Keycloak 26.2.10
  • RHSA-2025:18889 Released 2025-10-21 · Red Hat rating Important
    Red Hat build of Keycloak 26.2.10 Images Security Update
    • Red Hat build of Keycloak 26.2 rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator
  • RHSA-2025:18255 Released 2025-10-16 · Red Hat rating Important
    Red Hat build of Keycloak 26.0.16 Update
    • Red Hat build of Keycloak 26.0 rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator
Show 1 more Red Hat advisories
  • RHSA-2025:18254 Released 2025-10-16 · Red Hat rating Important
    Red Hat build of Keycloak 26.0.16 Images Update
    • Red Hat build of Keycloak 26.0.16

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat build of Keycloak 26.0Fixed RHSA-2025:18255
Red Hat build of Keycloak 26.0.16Fixed RHSA-2025:18254
Red Hat build of Keycloak 26.2Fixed RHSA-2025:18889
Red Hat build of Keycloak 26.2.10Fixed RHSA-2025:18890

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-11419
  2. 2026-10-03 Alias added: GHSA-q8hq-4h99-fj7x

References

Advisory 5

Other 6

  • 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