CVE-2026-86247: CWE-366 Race condition within a thread in Apache Software Foundation Apache Tomcat Native
A race condition vulnerability in Apache Tomcat Native allows client certificate verification requirements to be downgraded under certain configurations. This affects versions from 2.0.0 through 2.0.15 and 1.3.0 through 1.3.8. The issue is fixed in versions 2.0.16 and 1.3.9.
AI Analysis
Technical Summary
CVE-2026-86247 is a race condition vulnerability (CWE-366) within a thread in Apache Tomcat Native. This flaw permits the downgrading of client certificate verification requirements in some configurations, potentially weakening security controls. The vulnerability affects Apache Tomcat Native versions 2.0.0 through 2.0.15 and 1.3.0 through 1.3.8. The Apache Software Foundation has addressed this issue in versions 2.0.16 and 1.3.9.
Potential Impact
The vulnerability allows client certificate verification requirements to be downgraded, which could reduce the effectiveness of authentication mechanisms relying on client certificates. This weakening may lead to unauthorized access or reduced security assurance in affected deployments.
Mitigation Recommendations
Users should upgrade Apache Tomcat Native to version 2.0.16 or 1.3.9, where this race condition vulnerability has been fixed. Applying these updates will restore proper client certificate verification enforcement.
CVE-2026-86247: CWE-366 Race condition within a thread in Apache Software Foundation Apache Tomcat Native
Description
A race condition vulnerability in Apache Tomcat Native allows client certificate verification requirements to be downgraded under certain configurations. This affects versions from 2.0.0 through 2.0.15 and 1.3.0 through 1.3.8. The issue is fixed in versions 2.0.16 and 1.3.9.
Affected software
Apache Software Foundation
Apache Tomcat Native
pkg:github/apache/tomcat-nativeRun 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-2026-86247 is a race condition vulnerability (CWE-366) within a thread in Apache Tomcat Native. This flaw permits the downgrading of client certificate verification requirements in some configurations, potentially weakening security controls. The vulnerability affects Apache Tomcat Native versions 2.0.0 through 2.0.15 and 1.3.0 through 1.3.8. The Apache Software Foundation has addressed this issue in versions 2.0.16 and 1.3.9.
Potential Impact
The vulnerability allows client certificate verification requirements to be downgraded, which could reduce the effectiveness of authentication mechanisms relying on client certificates. This weakening may lead to unauthorized access or reduced security assurance in affected deployments.
Mitigation Recommendations
Users should upgrade Apache Tomcat Native to version 2.0.16 or 1.3.9, where this race condition vulnerability has been fixed. Applying these updates will restore proper client certificate verification enforcement.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-09-06T10:13:13.570Z
- State
- PUBLISHED
Threat ID: 6ab3ca9bf7a7c54106c73e0d
Added to database: 09/23/2026, 12:48:27 UTC
Last enriched: 09/23/2026, 13:03:06 UTC
Last updated: 09/23/2026, 13:07:37 UTC
Views: 4
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