CVE-2026-86247
High
Description
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.
SeverityHigh
CVSS7.4
Exploit probability—
Product
Apache Tomcat Native
PublishedSep 23, 2026
First seenSep 23, 2026
Weakness typeCWE-366CWE-366
How to fix
Update
- apache tomcat_native1.3.9, 2.0.16 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| apache tomcat_native | 1.3.0 ≤ v < 1.3.9, 2.0.0 ≤ v < 2.0.16 | 1.3.9, 2.0.16 |
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