Blind SSRF in Keycloak X.509 authenticator via CRL and OCSP URLs
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-918 and the CVSS impact.
Summary
The X.509 client-certificate authenticator in Keycloak fetches CRL Distribution Points or OCSP URLs when revocation checks are enabled. An unauthenticated remote attacker can supply a crafted certificate that makes Keycloak send outbound requests to internal or external endpoints before validation completes, a blind server-side request forgery (CWE-918).
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
A flaw was found in the X.509 client-certificate authenticator of Keycloak, a solution for identity and access management. The issue occurs when the server is configured to check certificate revocation using CRL Distribution Points or OCSP. An attacker can provide a specially crafted certificate that points to a malicious server, causing Keycloak to make unauthorized outbound requests to internal or external endpoints before the certificate is fully validated. This can lead to a blind server-side request forgery (SSRF) attack.
Why it matters now
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
Remediation
The sources list no fixed version for Red Hat Build of Keycloak. Red Hat rates this Moderate and gives no fix plan for Red Hat Build of Keycloak. Red Hat Single Sign-On 7 is not affected.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Build of Keycloak | Affected | No fix yet |
Not affected: 1 product
- Red Hat Single Sign-On 7
Timeline
- 2026-10-05 Threatist record created from CVE-2026-105301
- 2026-10-05 Alias added: GHSA-hg66-m76j-q2rm
- 2026-10-05 Affected versions changed · Red Hat
- 2026-10-05 CVSS score added · Red Hat
References
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Sources
- CVE-2026-105301 · CVE Program
- CVE-2026-105301 · NVD
- FIRST EPSS
- GHSA-hg66-m76j-q2rm · GitHub Advisory Database · CC BY 4.0
- CVE-2026-105301 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences