CVE-2026-117691
Keycloak-services: keycloak-services: saml redirect binding signature bypass via percent-encoded parameter names
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.
INFO
Published Date :
Nov. 5, 2026, 2:17 p.m.
Last Modified :
Nov. 5, 2026, 2:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-117691
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 53f830b8-0a3f-465b-8143-3b8a9948e749 | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update Keycloak to the latest version.
- Ensure SAML signature verification is robust.
- Validate all incoming SAML parameters.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-117691.
| URL | Resource |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-117691 | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2561977 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-117691 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-117691
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-117691 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-117691 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Nov. 05, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-347 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/117xxx/CVE-2026-117691.json">CVE-2026-117691</a> Added Reference https://access.redhat.com/security/cve/CVE-2026-117691 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2561977