Description
A flaw was found in the Dynamic Client Registration (DCR) component of Keycloak, an identity and access management solution. The default DCR policy fails to properly validate the claim path for User Property mappers, allowing them to write values to sensitive internal claim locations. An attacker with a standard user account and a limited Initial Access Token can exploit this to forge administrative roles in their access token. This allows the attacker to take over other clients, steal confidential secrets, and potentially gain full administrative control over the realm.
Affected products
redhat: build of keycloak; redhat: data grid; redhat: jboss enterprise application platform expansion pack; redhat: single sign-on
References6
- access.redhat.com/errata/RHSA-2026:50846 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:50847 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:50848 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:50849 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-16102 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2501735 Issue Tracking
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 40 · as of 13 November 2026
- CWE
- CWE-551CWE-284
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.