CVE-2026-11800

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-11800
A flaw was found in Keycloak. This JWT algorithm confusion vulnerability in the JWT Authorization Grant flow allows an attacker with valid client credentials to bypass signature verification. By forging an assertion, the attacker can create unauthorized access tokens. This enables the attacker to impersonate any federated user linked to the affected Identity Provider, leading to unauthorized access and potential privilege escalation.

8.1 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References
Link Resource
https://access.redhat.com/errata/RHSA-2026:30083 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:30084 Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-11800 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2487006 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:30083 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:30084 Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-11800 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2487006 Vendor Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-11800.json Vendor Advisory
Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*
History

01 Jul 2026, 18:35

Type Values Removed Values Added
References () https://access.redhat.com/errata/RHSA-2026:30083 - () https://access.redhat.com/errata/RHSA-2026:30083 - Vendor Advisory
References () https://access.redhat.com/errata/RHSA-2026:30084 - () https://access.redhat.com/errata/RHSA-2026:30084 - Vendor Advisory
References () https://access.redhat.com/security/cve/CVE-2026-11800 - () https://access.redhat.com/security/cve/CVE-2026-11800 - Vendor Advisory
References () https://bugzilla.redhat.com/show_bug.cgi?id=2487006 - () https://bugzilla.redhat.com/show_bug.cgi?id=2487006 - Vendor Advisory
References () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-11800.json - () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-11800.json - Vendor Advisory
First Time Redhat build Of Keycloak
Redhat
CPE cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*

30 Jun 2026, 03:17

Type Values Removed Values Added
References
  • () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-11800.json -
References () https://access.redhat.com/errata/RHSA-2026:30083 - () https://access.redhat.com/errata/RHSA-2026:30083 -
References () https://access.redhat.com/errata/RHSA-2026:30084 - () https://access.redhat.com/errata/RHSA-2026:30084 -
References () https://access.redhat.com/security/cve/CVE-2026-11800 - () https://access.redhat.com/security/cve/CVE-2026-11800 -
References () https://bugzilla.redhat.com/show_bug.cgi?id=2487006 - () https://bugzilla.redhat.com/show_bug.cgi?id=2487006 -

25 Jun 2026, 22:17

Type Values Removed Values Added
New CVE
Information

Published : 2026-06-25 22:17

Updated : 2026-07-15 02:18

NVD link : CVE-2026-11800

Mitre link : CVE-2026-11800

CVE.ORG link : CVE-2026-11800

JSON object : View

Products Affected

redhat

  • build_of_keycloak
CWE
CWE-347

Improper Verification of Cryptographic Signature