CVE-2025-11537: Keycloak quarkus server Keycloak Logs Sensitive Headers Vulnerability

MODERATE
Advisory Identifier: GHSA-gv3v-2cpp-3pmq
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CVSS 5.0
CWE-117
Published
Advisory Summary

CVE-2025-11537 is a MODERATE (CVSS 5.0) keycloak logs sensitive headers vulnerability (CWE-117: Improper Output Neutralization for Logs) affecting Keycloak quarkus server libraries in the Maven ecosystem. The issue involves keycloak logs sensitive headers. Remediation is available by upgrading affected packages to version 26.5.6.

CVE-2025-11537 at a Glance

CVE Identifier CVE-2025-11537
GHSA Identifier GHSA-gv3v-2cpp-3pmq
Severity MODERATE
CVSS v3.1 Base Score 5.0
CWE Classification CWE-117: Improper Output Neutralization for Logs
Affected Product Keycloak quarkus server
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 5.0

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

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

How to Fix CVE-2025-11537

To remediate this vulnerability, upgrade all affected Keycloak quarkus server 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-quarkus-server fixed: 26.5.6 
<dependency>
    <groupId>org.keycloak</groupId>
    <artifactId>keycloak-quarkus-server</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-2025-11537, 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 quarkus server 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-117: Improper Output Neutralization for Logs, where the product constructs a log message from external input, but it does not neutralize or incorrectly neutralizes special elements when the message is written to a log file. In Keycloak quarkus server, 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. When the logging format is configured to a verbose, user-supplied pattern (such as the pre-defined 'long' pattern), sensitive headers including Authorization and Cookie are disclosed to the logs in cleartext. An attacker with read access to the log files can extract these credentials (e.g., bearer tokens, session cookies) and use them to impersonate users, leading to a full account compromise. Patches are available, see: - https://github.com/keycloak/keycloak/releases/tag/26.4.11 - https://github.com/keycloak/keycloak/releases/tag/26.5.6 - https://github.com/keycloak/keycloak/releases/tag/26.6.0

CVE-2025-11537 Affected Keycloak quarkus server Versions

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

References

NVD — CVE-2025-11537 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-11537
Security Fix Commit FIX COMMIT
https://github.com/keycloak/keycloak/commit/137a35c1109ff43a305f26264978a3ea21452373
Security Fix Commit FIX COMMIT
https://github.com/keycloak/keycloak/commit/5a3cdb7c4ccbf83ffc926f70d655a60269d7207b
Security Fix Commit FIX COMMIT
https://github.com/keycloak/keycloak/commit/9622f550a6e565b29a3a37454421f08626791a6c
Keycloak quarkus server Security Information SECURITY
https://access.redhat.com/security/cve/CVE-2025-11537
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2402616
Keycloak quarkus server Source Repository REPOSITORY
https://github.com/keycloak/keycloak
www.keycloak.org/server/logging WEB
https://www.keycloak.org/server/logging#_change_log_formatpattern

Frequently Asked Questions

What is CVE-2025-11537?
CVE-2025-11537 is a security vulnerability in Keycloak quarkus server involving Keycloak logs sensitive headers under CWE-117: Improper Output Neutralization for Logs.
Which Keycloak quarkus server versions are affected?
Affected versions include releases prior to 26.5.6 across affected packages: org.keycloak:keycloak-quarkus-server.
What version fixes CVE-2025-11537?
Upgrading to 26.5.6 (or the latest patched release for your respective branch) resolves the vulnerability.
Is keycloak-quarkus-server affected?
Yes, org.keycloak:keycloak-quarkus-server 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-2025-11537?
CVE-2025-11537 has a CVSS v3.1 base score of 5.0 (MODERATE) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2025-11537?
CVE-2025-11537 is classified under CWE-117: Improper Output Neutralization for Logs (The product constructs a log message from external input, but it does not neutralize or incorrectly neutralizes special elements when the message is written to a log file.).
How can I check Maven dependencies for CVE-2025-11537?
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-gv3v-2cpp-3pmq",
  "modified" : "2026-04-08T21:55:47Z",
  "published" : "2026-02-10T12:30:28Z",
  "aliases" : [ "CVE-2025-11537" ],
  "summary" : "Keycloak logs sensitive headers",
  "details" : "A flaw was found in Keycloak. When the logging format is configured to a verbose, user-supplied pattern (such as the pre-defined 'long' pattern), sensitive headers including Authorization and Cookie are disclosed to the logs in cleartext. An attacker with read access to the log files can extract these credentials (e.g., bearer tokens, session cookies) and use them to impersonate users, leading to a full account compromise.\n\nPatches are available, see:\n\n- https://github.com/keycloak/keycloak/releases/tag/26.4.11\n- https://github.com/keycloak/keycloak/releases/tag/26.5.6\n- https://github.com/keycloak/keycloak/releases/tag/26.6.0",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.keycloak:keycloak-quarkus-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "26.5.6"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-11537"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/commit/137a35c1109ff43a305f26264978a3ea21452373"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/commit/5a3cdb7c4ccbf83ffc926f70d655a60269d7207b"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/keycloak/keycloak/commit/9622f550a6e565b29a3a37454421f08626791a6c"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/security/cve/CVE-2025-11537"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2402616"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/keycloak/keycloak"
  }, {
    "type" : "WEB",
    "url" : "https://www.keycloak.org/server/logging#_change_log_formatpattern"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-117" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-02-11T19:08:55Z",
    "nvd_published_at" : "2026-02-10T11:16:09Z"
  }
}