CVE-2026-86243

High

Description

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.

SeverityHigh

CVSS7.5

Exploit probability—

Product

Apache Tomcat Native

PublishedSep 23, 2026

First seenSep 23, 2026

Weakness typeCWE-126CWE-126

How to fix

Update

apache tomcat_native1.3.9, 2.0.16 or later

Vendor advisories

lists.apache.org/thread/8p4jf02w54m22x0cwpq2x53w3ov8o557

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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