CVE-2026-3009: Keycloak services Keycloak Allows Authentication Using An Vulnerability

HIGH
Advisory Identifier: GHSA-m297-3jv9-m927
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CVSS 8.1
CWE-285 CWE-863
Published
Advisory Summary

CVE-2026-3009 is a HIGH (CVSS 8.1) keycloak allows authentication using an vulnerability (CWE-285: Improper Authorization) affecting Keycloak services libraries in the Maven ecosystem. The issue involves keycloak allows authentication using an identity provider (idp) even after it has been disabled by an administrator. Remediation is available by upgrading affected packages to version 26.5.5.

CVE-2026-3009 at a Glance

CVE Identifier CVE-2026-3009
GHSA Identifier GHSA-m297-3jv9-m927
Severity HIGH
CVSS v3.1 Base Score 8.1
CWE Classification CWE-285: Improper Authorization
Affected Product Keycloak services
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 8.1

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

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
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-2026-3009

To remediate this vulnerability, upgrade all affected Keycloak services 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: 26.5.5 
<dependency>
    <groupId>org.keycloak</groupId>
    <artifactId>keycloak-services</artifactId>
    <version>26.5.5</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-2026-3009, 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 services in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 26.5.5), 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-285: Improper Authorization, where the product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. In Keycloak services, 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 security flaw in the IdentityBrokerService.performLogin endpoint of Keycloak allows authentication to proceed using an Identity Provider (IdP) even after it has been disabled by an administrator. An attacker who knows the IdP alias can reuse a previously generated login request to bypass the administrative restriction. This undermines access control enforcement and may allow unauthorized authentication through a disabled external provider.

CVE-2026-3009 Affected Keycloak services Versions

1 component(s)
Fixed Versions:
26.5.5
Product / Package Ecosystem Affected Versions Fixed Version
org.keycloak:keycloak-services
maven/org.keycloak/keycloak-services
Maven
< 26.5.5
26.5.5

References

NVD — CVE-2026-3009 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-3009
Keycloak services Source Repository REPOSITORY
https://github.com/keycloak/keycloak/issues/46911
Security Fix Commit FIX COMMIT
https://github.com/keycloak/keycloak/commit/4fd5367e6cc28cfa68fb2240fc459c12b1fdbf2a
access.redhat.com/errata/rhsa-2026:39... WEB
https://access.redhat.com/errata/RHSA-2026:3947
access.redhat.com/errata/rhsa-2026:39... WEB
https://access.redhat.com/errata/RHSA-2026:3948
Keycloak services Security Information SECURITY
https://access.redhat.com/security/cve/CVE-2026-3009
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2441867
Keycloak services Source Repository REPOSITORY
https://github.com/keycloak/keycloak
Keycloak services Release RELEASE
https://github.com/keycloak/keycloak/releases/tag/26.5.5

Frequently Asked Questions

What is CVE-2026-3009?
CVE-2026-3009 is a security vulnerability in Keycloak services involving Keycloak allows authentication using an Identity Provider (IdP) even after it has been disabled by an administrator under CWE-285: Improper Authorization.
Which Keycloak services versions are affected?
Affected versions include releases prior to 26.5.5 across affected packages: org.keycloak:keycloak-services.
What version fixes CVE-2026-3009?
Upgrading to 26.5.5 (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 26.5.5. Upgrade your dependency to 26.5.5 or later.
What is the CVSS score of CVE-2026-3009?
CVE-2026-3009 has a CVSS v3.1 base score of 8.1 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2026-3009?
CVE-2026-3009 is classified under CWE-285: Improper Authorization (The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.).
How can I check Maven dependencies for CVE-2026-3009?
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-m297-3jv9-m927",
  "modified" : "2026-03-06T22:28:28Z",
  "published" : "2026-03-05T21:30:48Z",
  "aliases" : [ "CVE-2026-3009" ],
  "summary" : "Keycloak allows authentication using an Identity Provider (IdP) even after it has been disabled by an administrator",
  "details" : "A security flaw in the IdentityBrokerService.performLogin endpoint of Keycloak allows authentication to proceed using an Identity Provider (IdP) even after it has been disabled by an administrator. An attacker who knows the IdP alias can reuse a previously generated login request to bypass the administrative restriction. This undermines access control enforcement and may allow unauthorized authentication through a disabled external provider.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/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" : "26.5.5"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-3009"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/issues/46911"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/commit/4fd5367e6cc28cfa68fb2240fc459c12b1fdbf2a"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:3947"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:3948"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/security/cve/CVE-2026-3009"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2441867"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/keycloak/keycloak"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/releases/tag/26.5.5"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-285", "CWE-863" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-06T22:28:28Z",
    "nvd_published_at" : "2026-03-05T19:16:18Z"
  }
}