CVE-2026-86243

Buffer over-read vulnerability in Apache Tomcat Native during the TLS handshake permits a malicious user to trigger a DoS via a JVM crash. This issue affects Apache Tomcat Native: from 2.0.0 through 2.0.15, from 1.3.0 through 1.3.8. Earlier, unsupported versions may also be affected. Users are recommended to upgrade to version 1.3.9 or 2.0.16, which fix the issue.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://lists.apache.org/thread/8p4jf02w54m22x0cwpq2x53w3ov8o557	Vendor Advisory Mailing List
http://www.openwall.com/lists/oss-security/2026/09/23/31	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, 13:53

Type	Values Removed	Values Added
References	~~() https://lists.apache.org/thread/8p4jf02w54m22x0cwpq2x53w3ov8o557 -~~	() https://lists.apache.org/thread/8p4jf02w54m22x0cwpq2x53w3ov8o557 - Vendor Advisory, Mailing List
References	~~() http://www.openwall.com/lists/oss-security/2026/09/23/31 -~~	() http://www.openwall.com/lists/oss-security/2026/09/23/31 - Mailing List, Third Party Advisory
First Time		Apache Apache tomcat Native
CPE		cpe:2.3:a:apache:tomcat_native::::::::

23 Sep 2026, 19:19

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/09/23/31 -

23 Sep 2026, 16:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5

23 Sep 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-23 13:17

Updated : 2026-10-06 13:53

NVD link : CVE-2026-86243

Mitre link : CVE-2026-86243

CVE.ORG link : CVE-2026-86243

JSON object : View

Products Affected

apache

tomcat_native

CWE

CWE-126

Buffer Over-read

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