CVE-2026-0871 Org.keycloak/keycloak-services: keycloak: unauthorized modification of unmanaged user attributes by administrators
Administrators can bypass restrictions to modify unmanaged user attributes, leading to unauthorized profile changes in Keycloak deployments.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-0871?
CVE-2026-0871 is a medium-severity missing authorization vulnerability in Redhat Build of Keycloak, published on 27 Feb 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
A flaw was found in Keycloak. An administrator with `manage-users` permission can bypass the "Only administrators can view" setting for unmanaged attributes, allowing them to modify these attributes. This improper access control can lead to unauthorized changes to user profiles, even when the system is configured to restrict such modifications.
Weakness: CWE-266
Which versions are affected by CVE-2026-0871?
3 open source packages ship an affected version, including org.keycloak:keycloak-server-spi-private and keycloak. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
org.keycloak:keycloak-server-spi-private Maven | All versions | 26.5.2 |
org.keycloak:keycloak-server-spi-private Maven | All versions | 26.5.2 |
keycloak Bitnami | All versions | 26.4.9 |
Products include Redhat Build of Keycloak, Redhat Keycloak.
How do I fix CVE-2026-0871?
Upgrade org.keycloak:keycloak-server-spi-private to 26.5.2 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-0871 being exploited?
There is no known exploitation of CVE-2026-0871 in the wild and no public exploit code.
Other vulnerabilities in Redhat Build of Keycloak
- CVE-2026-15572 Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation
- CVE-2026-3047 Keycloak SAML Broken has Authentication Bypass by Primary Weakness
- CVE-2026-15573 Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher
- CVE-2026-16102 Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers
- CVE-2026-1609 Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users
Sources
Also known as BIT-keycloak-2026-0871, ECHO-738b-62c7-508f, GHSA-v4jw-m6rm-399h, MINI-mhh6-r3xq-h4c4, MINI-rpvp-r4gf-cgxh.