CVE-2026-3911: Keycloak Information Disclosure Of Disabled User Vulnerability

LOW
Advisory Identifier: GHSA-xh32-c9wx-phrp
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CVSS 2.7
CWE-359
Published
Advisory Summary

CVE-2026-3911 is a LOW (CVSS 2.7) information disclosure of disabled user vulnerability (CWE-359: Exposure of Private Personal Information to an Unauthorized Actor) affecting Keycloak libraries in the Maven ecosystem. The issue involves information disclosure of disabled user attributes via administrative endpoint. Remediation is available in the latest vendor maintenance releases.

CVE-2026-3911 at a Glance

CVE Identifier CVE-2026-3911
GHSA Identifier GHSA-xh32-c9wx-phrp
Severity LOW
CVSS v3.1 Base Score 2.7
CWE Classification CWE-359: Exposure of Private Personal Information to an Unauthorized Actor
Affected Product Keycloak
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 2.7

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:L/I:N/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 Low (C:L)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-3911

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: Latest secure release 
<dependency>
    <groupId>org.keycloak</groupId>
    <artifactId>keycloak-services</artifactId>
    <version>Latest secure release</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-2026-3911, 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 the patched release), 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-359: Exposure of Private Personal Information to an Unauthorized Actor, where the product does not properly prevent a person's private, personal information from being accessed by actors who either (1) are not explicitly authorized to access the information or (2) do not have the implicit consent of the person about whom the information is collected. 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 authenticated user with the view-users role could exploit a vulnerability in the UserResource component. By accessing a specific administrative endpoint, this user could improperly retrieve user attributes that were configured to be hidden. This unauthorized information disclosure could expose sensitive user data.

CVE-2026-3911 Affected Keycloak Versions

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

References

NVD — CVE-2026-3911 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-3911
Keycloak Source Repository REPOSITORY
https://github.com/keycloak/keycloak/issues/46922
Keycloak Source Repository REPOSITORY
https://github.com/keycloak/keycloak/pull/46923
Security Fix Commit FIX COMMIT
https://github.com/keycloak/keycloak/commit/215bc1e27230f2a66670ed70262248b5f5254eb9
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-2026-3911
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2446392
Keycloak Source Repository REPOSITORY
https://github.com/keycloak/keycloak

Frequently Asked Questions

What is CVE-2026-3911?
CVE-2026-3911 is a security vulnerability in Keycloak involving Information disclosure of disabled user attributes via administrative endpoint under CWE-359: Exposure of Private Personal Information to an Unauthorized Actor.
Which Keycloak versions are affected?
Affected versions include releases prior to current release patches across affected packages: org.keycloak:keycloak-services.
What version fixes CVE-2026-3911?
Upgrading to current release patches (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 Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2026-3911?
CVE-2026-3911 has a CVSS v3.1 base score of 2.7 (LOW) with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N.
What CWE is associated with CVE-2026-3911?
CVE-2026-3911 is classified under CWE-359: Exposure of Private Personal Information to an Unauthorized Actor (The product does not properly prevent a person's private, personal information from being accessed by actors who either (1) are not explicitly authorized to access the information or (2) do not have the implicit consent of the person about whom the information is collected.).
How can I check Maven dependencies for CVE-2026-3911?
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-xh32-c9wx-phrp",
  "modified" : "2026-04-02T15:31:35Z",
  "published" : "2026-03-11T06:31:41Z",
  "aliases" : [ "CVE-2026-3911" ],
  "summary" : "Keycloak: Information disclosure of disabled user attributes via administrative endpoint",
  "details" : "A flaw was found in Keycloak. An authenticated user with the view-users role could exploit a vulnerability in the UserResource component. By accessing a specific administrative endpoint, this user could improperly retrieve user attributes that were configured to be hidden. This unauthorized information disclosure could expose sensitive user data.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.keycloak:keycloak-services"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "26.5.5"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-3911"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/issues/46922"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/pull/46923"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/commit/215bc1e27230f2a66670ed70262248b5f5254eb9"
  }, {
    "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-2026-3911"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2446392"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/keycloak/keycloak"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-359" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-12T14:42:34Z",
    "nvd_published_at" : "2026-03-11T06:17:15Z"
  }
}