Apache Tomcat Native up to 1.3.8/2.0.15 race condition

Summaryinfo

A vulnerability categorized as critical has been discovered in Apache Tomcat Native up to 1.3.8/2.0.15. Affected by this issue is some unknown functionality. The manipulation results in race condition. This vulnerability was named CVE-2026-86247. The attack may be performed from remote. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apache Tomcat Native up to 1.3.8/2.0.15. It has been classified as critical. Affected is an unknown functionality. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Race condition within a thread vulnerability in Apache Tomcat Native allowed client certificate verification requirements to be down-graded for some configurations. This issue affects Apache Tomcat Native: from 2.0.0 through 2.0.15, from 1.3.0 through 1.3.8. Unsupported versions may also be affected. Users are recommended to upgrade to version 2.0.16 or 1.3.9, which fixes the issue.

The advisory is shared for download at lists.apache.org. This vulnerability is traded as CVE-2026-86247 since 09/06/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/23/2026).

Upgrading to version 1.3.9 or 2.0.16 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Application Server Software

Vendor

• Apache

Name

• Tomcat Native

Version

• 1.3.0
• 1.3.1
• 1.3.2
• 1.3.3
• 1.3.4
• 1.3.5
• 1.3.6
• 1.3.7
• 1.3.8
• 2.0.0
• 2.0.1
• 2.0.2
• 2.0.3
• 2.0.4
• 2.0.5
• 2.0.6
• 2.0.7
• 2.0.8
• 2.0.9
• 2.0.10
• 2.0.11
• 2.0.12
• 2.0.13
• 2.0.14
• 2.0.15

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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