Access Control Flaw in Keycloak Allows Unauthorized User Profile Modifications
CVE-2026-0871

4.9MEDIUM

Key Information:

Vendor

Red Hat
Status
Red Hat Build Of Keycloak 26.4
Red Hat Build Of Keycloak 26.4.9
Red Hat Jboss Enterprise Application Platform 8
Red Hat Jboss Enterprise Application Platform Expansion Pack
Vendor
CVE Published:
27 February 2026

What is CVE-2026-0871?

A significant issue has been identified in Keycloak where an administrator with 'manage-users' permissions can bypass the configuration settings intended to restrict access to unmanaged attributes. This flaw permits unauthorized modifications to user profiles even in scenarios where the application is set to prevent such alterations. The failure to enforce proper access controls can lead to severe consequences, including unauthorized data manipulation, potentially compromising the integrity and security of user information.

Affected Version(s)

Red Hat build of Keycloak 26.4 26.4.9-1

Red Hat build of Keycloak 26.4 26.4-11

Red Hat build of Keycloak 26.4 26.4-10

References

https://access.redhat.com/errata/RHSA-2026:2365
vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:2366
vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-0871
vdb-entryx_refsource_REDHAT

CVSS V3.1

Score:
4.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.