Vulnerability details
CVE-2026-117691
Red Hat Build of Keycloak
Keycloak-services: keycloak-services: saml redirect binding signature bypass via percent-encoded parameter names
CVSS 3.1
9.1Critical
Official description
A flaw was found in the SAML HTTP-Redirect binding implementation of Keycloak. The issue occurs because the server processes percent-encoded parameter names (like %53AMLResponse) while the signature verification logic only checks literal parameter names. An attacker can use this discrepancy to provide a crafted, unsigned SAML message that the server processes instead of a legitimately signed one, leading to full account takeover of federated users.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 9.1Critical | 3.1 | CVEProject cvelistV5 (CNA) (redhat) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Red Hat | Red Hat Build of Keycloak | All | CVEProject cvelistV5 (CNA) |
References and advisories
3- https://access.redhat.com/errata/RHSA-2026:96039 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-117691 vdb-entryx_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2561977 issue-trackingx_refsource_REDHAT
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Details
- Published
- 2026-11-05
- Last updated
- 2026-11-07
- State
- Published
- Assigner (CNA)
- redhat
- Kolun priority
- 25 · Low
Exploit prediction (EPSS)
0.28%
Probability of exploitation in 30 days
20.8%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- Yes
- Exploitation
- None
- Technical impact
- Total
Weaknesses (CWE)
- CWE-347Improper Verification of Cryptographic Signature