Medium severity · published Jun 30, 2026
CVE-2026-12388
Keycloak-broker: keycloak: privilege escalation to realm administrator via improper authorization in identity provider mapper
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat Build of Keycloak · Red Hat
All versions, or not specified · source: vendor
BO
Build OF Keycloak · Redhat
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-12388
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-12388
Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-12388
Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2489140
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