Race condition in Apache Tomcat Native - CVE-2026-86247
Published: September 24, 2026
Vulnerability identifier: #VU151966
CSH Severity: Medium
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-86247
CWE-ID: CWE-362
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass client certificate verification requirements.
The vulnerability exists due to a race condition in Apache Tomcat Native when verifying client certificates. A remote attacker can exploit the race condition to bypass client certificate verification requirements.
Only some configurations are affected.
Affected software
Apache Tomcat Native
How to mitigate CVE-2026-86247
Install security update from vendor's website.
Apache Tomcat Native - addressed in versions 1.3.9, 2.0.16