Description
A flaw was found in Keycloak. An improper Access Control vulnerability in Keycloak’s User-Managed Access (UMA) resource_set endpoint allows attackers with valid credentials to bypass the allowRemoteResourceManagement=false restriction. This occurs due to incomplete enforcement of access control checks on PUT operations to the resource_set endpoint. This issue enables unauthorized modification of protected resources, impacting data integrity.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.4.12 | — | — |
| Red Hat | Red Hat Build of Keycloak | — | — |
| Red Hat | Red Hat JBoss Enterprise Application Platform 8 | — | — |
| Red Hat | Red Hat JBoss Enterprise Application Platform Expansion Pack | — | — |
| Red Hat | Red Hat Single Sign-On 7 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | keycloak-26.5 +2 | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.keycloak:keycloak-services | <= 26.6.0 | — | GHSA-4pgc-gfrr-wcmg |
Advisories 1
- WID-SEC-2026-0821 Keycloak: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 30, 2026
References
- RHSA-2026:19596 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-4628 vdb-entry
- RHBZ#2450240 issue-tracking