CVE-2026-86247

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.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://lists.apache.org/thread/obsson6zhvfg0wsp2bx602l61ltj87r1	Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/09/23/33	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:apache:tomcat_native::::::::
	cpe:2.3:a:apache:tomcat_native::::::::

History

06 Oct 2026, 13:46

Type	Values Removed	Values Added
CPE		cpe:2.3:a:apache:tomcat_native::::::::
First Time		Apache Apache tomcat Native
References	~~() https://lists.apache.org/thread/obsson6zhvfg0wsp2bx602l61ltj87r1 -~~	() https://lists.apache.org/thread/obsson6zhvfg0wsp2bx602l61ltj87r1 - Vendor Advisory
References	~~() http://www.openwall.com/lists/oss-security/2026/09/23/33 -~~	() http://www.openwall.com/lists/oss-security/2026/09/23/33 - Mailing List, Third Party Advisory

23 Sep 2026, 19:19

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/09/23/33 -

23 Sep 2026, 16:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.4

23 Sep 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-23 13:17

Updated : 2026-10-06 13:46

NVD link : CVE-2026-86247

Mitre link : CVE-2026-86247

CVE.ORG link : CVE-2026-86247

JSON object : View

Products Affected

apache

tomcat_native

CWE

CWE-366

Race Condition within a Thread

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