CVE-2026-34487: Apache Tomcat Apache Tomcat Vulnerable To Insertion Vulnerability

HIGH
Advisory Identifier: GHSA-x4m4-345f-5h5g
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CVSS 7.5
CWE-532
Published
Advisory Summary

CVE-2026-34487 is a HIGH (CVSS 7.5) apache tomcat vulnerable to insertion vulnerability (CWE-532: Insertion of Sensitive Information into Log File) affecting Apache Tomcat libraries in the Maven ecosystem. The issue involves apache tomcat vulnerable to insertion of sensitive information into log file. Remediation is available by upgrading affected packages to version 9.0.117, 10.1.54, 11.0.21.

CVE-2026-34487 at a Glance

CVE Identifier CVE-2026-34487
GHSA Identifier GHSA-x4m4-345f-5h5g
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-532: Insertion of Sensitive Information into Log File
Affected Product Apache Tomcat
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.5

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

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

How to Fix CVE-2026-34487

To remediate this vulnerability, upgrade all affected Apache Tomcat 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.apache.tomcat:tomcat-tribes fixed: 9.0.117 
<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat-tribes</artifactId>
    <version>9.0.117</version>
</dependency>
org.apache.tomcat:tomcat-tribes fixed: 10.1.54 
<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat-tribes</artifactId>
    <version>10.1.54</version>
</dependency>
org.apache.tomcat:tomcat-tribes fixed: 11.0.21 
<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat-tribes</artifactId>
    <version>11.0.21</version>
</dependency>
org.apache.tomcat:tomcat fixed: 9.0.117 
<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat</artifactId>
    <version>9.0.117</version>
</dependency>
org.apache.tomcat:tomcat fixed: 10.1.54 
<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat</artifactId>
    <version>10.1.54</version>
</dependency>
org.apache.tomcat:tomcat fixed: 11.0.21 
<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat</artifactId>
    <version>11.0.21</version>
</dependency>
org.apache.tomcat.embed:tomcat-embed-core fixed: 9.0.117 
<dependency>
    <groupId>org.apache.tomcat.embed</groupId>
    <artifactId>tomcat-embed-core</artifactId>
    <version>9.0.117</version>
</dependency>
org.apache.tomcat.embed:tomcat-embed-core fixed: 10.1.54 
<dependency>
    <groupId>org.apache.tomcat.embed</groupId>
    <artifactId>tomcat-embed-core</artifactId>
    <version>10.1.54</version>
</dependency>
org.apache.tomcat.embed:tomcat-embed-core fixed: 11.0.21 
<dependency>
    <groupId>org.apache.tomcat.embed</groupId>
    <artifactId>tomcat-embed-core</artifactId>
    <version>11.0.21</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.apache.tomcat

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-34487, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.apache.tomcat

Analyze the terminal output to locate any version of Apache Tomcat in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 9.0.117), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.apache.tomcat 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-532: Insertion of Sensitive Information into Log File, where the product writes sensitive information to a log file. In Apache Tomcat, 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

Insertion of Sensitive Information into Log File vulnerability in the cloud membership for clustering component of Apache Tomcat exposed the Kubernetes bearer token. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.20, from 10.1.0-M1 through 10.1.53, from 9.0.13 through 9.0.116. Users are recommended to upgrade to version 11.0.21, 10.1.54 or 9.0.117, which fix the issue.

CVE-2026-34487 Affected Apache Tomcat Versions

9 component(s)
Fixed Versions:
9.0.11710.1.5411.0.21
Product / Package Ecosystem Affected Versions Fixed Version
org.apache.tomcat:tomcat-tribes
maven/org.apache.tomcat/tomcat-tribes
Maven
≥ 9.0.13
< 9.0.117
9.0.117
org.apache.tomcat:tomcat-tribes
maven/org.apache.tomcat/tomcat-tribes
Maven
≥ 10.1.0-M1
< 10.1.54
10.1.54
org.apache.tomcat:tomcat-tribes
maven/org.apache.tomcat/tomcat-tribes
Maven
≥ 11.0.0-M1
< 11.0.21
11.0.21
org.apache.tomcat:tomcat
maven/org.apache.tomcat/tomcat
Maven
≥ 9.0.13
< 9.0.117
9.0.117
org.apache.tomcat:tomcat
maven/org.apache.tomcat/tomcat
Maven
≥ 10.1.0-M1
< 10.1.54
10.1.54
org.apache.tomcat:tomcat
maven/org.apache.tomcat/tomcat
Maven
≥ 11.0.0-M1
< 11.0.21
11.0.21
org.apache.tomcat.embed:tomcat-embed-core
maven/org.apache.tomcat.embed/tomcat-embed-core
Maven
≥ 9.0.13
< 9.0.117
9.0.117
org.apache.tomcat.embed:tomcat-embed-core
maven/org.apache.tomcat.embed/tomcat-embed-core
Maven
≥ 10.1.0-M1
< 10.1.54
10.1.54
org.apache.tomcat.embed:tomcat-embed-core
maven/org.apache.tomcat.embed/tomcat-embed-core
Maven
≥ 11.0.0-M1
< 11.0.21
11.0.21

References

NVD — CVE-2026-34487 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34487
Security Fix Commit FIX COMMIT
https://github.com/apache/tomcat/commit/301bc6efbf72feb14dacfdfa3f50372182736150
Security Fix Commit FIX COMMIT
https://github.com/apache/tomcat/commit/5eff2a773b8b728083e5195b3183df1b9e12a03d
Security Fix Commit FIX COMMIT
https://github.com/apache/tomcat/commit/f593292a082e5ef9336a8db2b4b522f7f3e36976
Apache Tomcat Source Repository REPOSITORY
https://github.com/apache/tomcat
lists.apache.org/thread/4xpkwolpkrj8... WEB
https://lists.apache.org/thread/4xpkwolpkrj8v5xzp5nyovtlqp3y850h
Apache Tomcat Security Information SECURITY
https://tomcat.apache.org/security-10.html
Apache Tomcat Security Information SECURITY
https://tomcat.apache.org/security-11.html
Apache Tomcat Security Information SECURITY
https://tomcat.apache.org/security-9.html
Apache Tomcat Security Information SECURITY
http://www.openwall.com/lists/oss-security/2026/04/09/28

Frequently Asked Questions

What is CVE-2026-34487?
CVE-2026-34487 is a security vulnerability in Apache Tomcat involving Apache Tomcat vulnerable to Insertion of Sensitive Information into Log File under CWE-532: Insertion of Sensitive Information into Log File.
Which Apache Tomcat versions are affected?
Affected versions include releases prior to 9.0.117, 10.1.54, 11.0.21 across affected packages: org.apache.tomcat:tomcat-tribes, org.apache.tomcat:tomcat, org.apache.tomcat.embed:tomcat-embed-core.
What version fixes CVE-2026-34487?
Upgrading to 9.0.117, 10.1.54, 11.0.21 (or the latest patched release for your respective branch) resolves the vulnerability.
Is tomcat-tribes affected?
Yes, org.apache.tomcat:tomcat-tribes is affected in releases prior to 9.0.117, 10.1.54, 11.0.21. Upgrade your dependency to 9.0.117, 10.1.54, 11.0.21 or later.
Is tomcat affected?
Yes, org.apache.tomcat:tomcat is affected in releases prior to 9.0.117, 10.1.54, 11.0.21. Upgrade your dependency to 9.0.117, 10.1.54, 11.0.21 or later.
What is the CVSS score of CVE-2026-34487?
CVE-2026-34487 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-34487?
CVE-2026-34487 is classified under CWE-532: Insertion of Sensitive Information into Log File (The product writes sensitive information to a log file.).
How can I check Maven dependencies for CVE-2026-34487?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.apache.tomcat'. 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-x4m4-345f-5h5g",
  "modified" : "2026-08-12T18:49:22Z",
  "published" : "2026-04-09T21:31:30Z",
  "aliases" : [ "CVE-2026-34487" ],
  "summary" : "Apache Tomcat vulnerable to Insertion of Sensitive Information into Log File",
  "details" : "Insertion of Sensitive Information into Log File vulnerability in the cloud membership for clustering component of Apache Tomcat exposed the Kubernetes bearer token.\n\nThis issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.20, from 10.1.0-M1 through 10.1.53, from 9.0.13 through 9.0.116.\n\nUsers are recommended to upgrade to version 11.0.21, 10.1.54 or 9.0.117, which fix the issue.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat:tomcat-tribes"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "9.0.13"
      }, {
        "fixed" : "9.0.117"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat:tomcat-tribes"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.1.0-M1"
      }, {
        "fixed" : "10.1.54"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat:tomcat-tribes"
    },
    "ranges" : [ {
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      }, {
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      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat:tomcat"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
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      }, {
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      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat:tomcat"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.1.0-M1"
      }, {
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      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat:tomcat"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.0.0-M1"
      }, {
        "fixed" : "11.0.21"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat.embed:tomcat-embed-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "9.0.13"
      }, {
        "fixed" : "9.0.117"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat.embed:tomcat-embed-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.1.0-M1"
      }, {
        "fixed" : "10.1.54"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.tomcat.embed:tomcat-embed-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.0.0-M1"
      }, {
        "fixed" : "11.0.21"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-34487"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/apache/tomcat/commit/301bc6efbf72feb14dacfdfa3f50372182736150"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/apache/tomcat/commit/5eff2a773b8b728083e5195b3183df1b9e12a03d"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/apache/tomcat/commit/f593292a082e5ef9336a8db2b4b522f7f3e36976"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/apache/tomcat"
  }, {
    "type" : "WEB",
    "url" : "https://lists.apache.org/thread/4xpkwolpkrj8v5xzp5nyovtlqp3y850h"
  }, {
    "type" : "WEB",
    "url" : "https://tomcat.apache.org/security-10.html"
  }, {
    "type" : "WEB",
    "url" : "https://tomcat.apache.org/security-11.html"
  }, {
    "type" : "WEB",
    "url" : "https://tomcat.apache.org/security-9.html"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2026/04/09/28"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-532" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-10T21:38:41Z",
    "nvd_published_at" : "2026-04-09T20:16:25Z"
  }
}