CVE-2026-3121: Keycloak Manage-clients Permission Escalates To Full Vulnerability

MODERATE
Advisory Identifier: GHSA-7xf9-4jfc-wgm4
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CVSS 6.5
CWE-266
Published
Advisory Summary

CVE-2026-3121 is a MODERATE (CVSS 6.5) manage-clients permission escalates to full vulnerability (CWE-266: Incorrect Privilege Assignment) affecting Keycloak libraries in the Maven ecosystem. The issue involves manage-clients permission escalates to full realm admin access. Remediation is available by upgrading affected packages to version 26.5.6.

CVE-2026-3121 at a Glance

CVE Identifier CVE-2026-3121
GHSA Identifier GHSA-7xf9-4jfc-wgm4
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-266: Incorrect Privilege Assignment
Affected Product Keycloak
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 6.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required High (PR:H)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2026-3121

To remediate this vulnerability, upgrade all affected Keycloak dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

org.keycloak:keycloak-services fixed: 26.5.6 
<dependency>
    <groupId>org.keycloak</groupId>
    <artifactId>keycloak-services</artifactId>
    <version>26.5.6</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=org.keycloak

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-3121, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.keycloak

Analyze the terminal output to locate any version of Keycloak in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 26.5.6), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.keycloak command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-266: Incorrect Privilege Assignment, where a product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor. In Keycloak, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A flaw was found in Keycloak. An administrator with `manage-clients` permission can exploit a misconfiguration where this permission is equivalent to `manage-permissions`. This allows the administrator to escalate privileges and gain control over roles, users, or other administrative functions within the realm. This privilege escalation can occur when admin permissions are enabled at the realm level.

CVE-2026-3121 Affected Keycloak Versions

1 component(s)
Fixed Versions:
26.5.6
Product / Package Ecosystem Affected Versions Fixed Version
org.keycloak:keycloak-services
maven/org.keycloak/keycloak-services
Maven
< 26.5.6
26.5.6

References

NVD — CVE-2026-3121 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-3121
Keycloak Source Repository REPOSITORY
https://github.com/keycloak/keycloak/issues/46719
Security Fix Commit FIX COMMIT
https://github.com/keycloak/keycloak/commit/79ab3110a257fb8d6f1a664c916687128094ed01
access.redhat.com/errata/rhsa-2026:64... WEB
https://access.redhat.com/errata/RHSA-2026:6477
access.redhat.com/errata/rhsa-2026:64... WEB
https://access.redhat.com/errata/RHSA-2026:6478
Keycloak Security Information SECURITY
https://access.redhat.com/security/cve/CVE-2026-3121
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2442277
Keycloak Source Repository REPOSITORY
https://github.com/keycloak/keycloak

Frequently Asked Questions

What is CVE-2026-3121?
CVE-2026-3121 is a security vulnerability in Keycloak involving manage-clients permission escalates to full realm admin access under CWE-266: Incorrect Privilege Assignment.
Which Keycloak versions are affected?
Affected versions include releases prior to 26.5.6 across affected packages: org.keycloak:keycloak-services.
What version fixes CVE-2026-3121?
Upgrading to 26.5.6 (or the latest patched release for your respective branch) resolves the vulnerability.
Is keycloak-services affected?
Yes, org.keycloak:keycloak-services is affected in releases prior to 26.5.6. Upgrade your dependency to 26.5.6 or later.
What is the CVSS score of CVE-2026-3121?
CVE-2026-3121 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2026-3121?
CVE-2026-3121 is classified under CWE-266: Incorrect Privilege Assignment (A product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor.).
How can I check Maven dependencies for CVE-2026-3121?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.keycloak'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-7xf9-4jfc-wgm4",
  "modified" : "2026-04-06T16:41:13Z",
  "published" : "2026-03-26T21:31:26Z",
  "aliases" : [ "CVE-2026-3121" ],
  "summary" : "Keycloak: manage-clients permission escalates to full realm admin access",
  "details" : "A flaw was found in Keycloak. An administrator with `manage-clients` permission can exploit a misconfiguration where this permission is equivalent to `manage-permissions`. This allows the administrator to escalate privileges and gain control over roles, users, or other administrative functions within the realm. This privilege escalation can occur when admin permissions are enabled at the realm level.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.keycloak:keycloak-services"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "26.5.6"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-3121"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/issues/46719"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/commit/79ab3110a257fb8d6f1a664c916687128094ed01"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:6477"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:6478"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/security/cve/CVE-2026-3121"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2442277"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/keycloak/keycloak"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-266" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-29T15:45:17Z",
    "nvd_published_at" : "2026-03-26T19:17:06Z"
  }
}