CVE-2026-78437: CWE-459 Incomplete cleanup in Apache Software Foundation Apache Tomcat
Incomplete cleanup vulnerability in Apache Tomcat allows a malformed request to potentially (depends on timing) cause one request from another user to fail. This issue affects Apache Tomcat: from 11.0.19 through 11.0.25, from 10.1.53 through 10.1.59, from 9.0.116 through 9.0.121. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
AI Analysis
Technical Summary
CVE-2026-78437 is an incomplete cleanup vulnerability in Apache Tomcat that allows a malformed request to potentially cause a request from another user to fail, depending on timing. The affected versions include Apache Tomcat 11.0.19 through 11.0.25, 10.1.53 through 10.1.59, and 9.0.116 through 9.0.121. The issue is resolved in versions 11.0.26, 10.1.60, and 9.0.122.
Potential Impact
The vulnerability may result in a denial of service for one user’s request caused by a malformed request from another user, potentially impacting availability of the affected Apache Tomcat server during the timing window.
Mitigation Recommendations
Users should upgrade to Apache Tomcat versions 11.0.26, 10.1.60, or 9.0.122 to remediate this vulnerability. These versions contain the official fix for the issue.
CVE-2026-78437: CWE-459 Incomplete cleanup in Apache Software Foundation Apache Tomcat
Description
Incomplete cleanup vulnerability in Apache Tomcat allows a malformed request to potentially (depends on timing) cause one request from another user to fail. This issue affects Apache Tomcat: from 11.0.19 through 11.0.25, from 10.1.53 through 10.1.59, from 9.0.116 through 9.0.121. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
CVSS v3.1
Score 7.3high
Affected software
Apache Software Foundation
Apache Tomcat
pkg:maven/org.apache.tomcat/tomcatRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-78437 is an incomplete cleanup vulnerability in Apache Tomcat that allows a malformed request to potentially cause a request from another user to fail, depending on timing. The affected versions include Apache Tomcat 11.0.19 through 11.0.25, 10.1.53 through 10.1.59, and 9.0.116 through 9.0.121. The issue is resolved in versions 11.0.26, 10.1.60, and 9.0.122.
Potential Impact
The vulnerability may result in a denial of service for one user’s request caused by a malformed request from another user, potentially impacting availability of the affected Apache Tomcat server during the timing window.
Mitigation Recommendations
Users should upgrade to Apache Tomcat versions 11.0.26, 10.1.60, or 9.0.122 to remediate this vulnerability. These versions contain the official fix for the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-08-24T16:10:49.885Z
- State
- PUBLISHED
Threat ID: 6ab3b90df7a7c54106b30f15
Added to database: 09/23/2026, 11:33:33 UTC
Last enriched: 09/23/2026, 11:48:46 UTC
Last updated: 09/24/2026, 02:51:55 UTC
Views: 11
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