CVE-2026-12388
A flaw was found in the Identity Provider (IdP) mapper component of Keycloak, which is used to manage how user information from external services is mapped to Keycloak users. An administrator with limited permissions to manage identity providers can exploit this flaw by creating a "Hardcoded Role" mapper that assigns high-level administrative roles (like realm-admin) to themselves or others. This allows a restricted administrator to bypass security checks and gain full control over the entire realm.
Executive briefing
The source record describes: A flaw was found in the Identity Provider (IdP) mapper component of Keycloak, which is used to manage how user information from external services is mapped to Keycloak users. An administrator with limited permissions to manage identity providers can exploit this flaw by creating a "Hardcoded Role" mapper that assigns high-level administrative roles (like realm-admin) to themselves or others. This allows a restricted administrator to bypass security checks and gain full control over the entire realm. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.
Evidence confidence: Moderate Evidence-derived, not an exploitability verdict
Severity & attack characteristics
CVSS vector:CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Technical explanation & impact
The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.
Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.
Weakness classification
CWE-266Affected products and versions
Products below are parsed from NVD vulnerable CPE configuration entries. Version boundaries are shown as published; verify applicability with the vendor.
| Vendor | Product | Version evidence |
|---|---|---|
| redhat | build_of_keycloak | Version not specified in CPE |
Remediation & validation
- Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
- Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
- Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
- Validate the remediation with a version check and vulnerability rescan, then retain change evidence.
No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.
Vendor advisories, patches & exploit references
- https://access.redhat.com/errata/RHSA-2026:95761 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:95762 VENDOR secalert@redhat.com
- https://access.redhat.com/security/cve/CVE-2026-12388 ADVISORY secalert@redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2489140 ADVISORY secalert@redhat.com