Quick answers
- Is CVE-2026-86247 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-86247 being exploited in the wild.
- How severe is CVE-2026-86247?
- High severity, with a CVSS score of 7.4, published 23 September 2026.
- Which products and versions are affected?
- Apache Tomcat Native 2.0.0 through 2.0.15, 1.3.0 through 1.3.8.
- Is there a fix for CVE-2026-86247?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-86247 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-86247?
- Check whether you run Apache Tomcat Native at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A race condition within a thread in Apache Tomcat Native allows client certificate verification requirements to be down-graded for some configurations. The vulnerability exists in versions 2.0.0-2.0.15 and 1.3.0-1.3.8. An attacker on the network can exploit this condition to bypass client certificate authentication protections; no user interaction or prior authentication is required.
Affected products
- Apache Tomcat Native 2.0.0 through 2.0.15, 1.3.0 through 1.3.8
Timeline
- 2026-09-23: disclosed