CVE-2026-18203

Published: Lug 31, 2026 Last Modified: Lug 31, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 6,5
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: high
Availability: none

Description

AI Translation Available

A flaw was found in the group policy evaluation logic of Keycloak, an identity and access management solution. When a group policy is set to extend permissions to child groups, the system incorrectly uses a simple text-based prefix check to verify group membership. This allows a user who belongs to a different group with a similar starting name to bypass security checks and gain unauthorized access to administrative functions or protected resources.

863

Incorrect Authorization

Incomplete
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Access Control Availability
Potential Impacts:
Read Application Data Read Files Or Directories Modify Application Data Modify Files Or Directories Gain Privileges Or Assume Identity Bypass Protection Mechanism Execute Unauthorized Code Or Commands Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Dos: Resource Consumption (Other)
Applicable Platforms
Technologies: Web Server, Database Server, Not Technology-Specific
Likelihood of Exploit: High
View CWE Details
https://access.redhat.com/security/cve/CVE-2026-18203
https://access.redhat.com/security/cve/CVE-2026-18203
https://bugzilla.redhat.com/show_bug.cgi?id=2508291
https://bugzilla.redhat.com/show_bug.cgi?id=2508291