SB2026092480 - Multiple vulnerabilities in Apache Tomcat Native



SB2026092480 - Multiple vulnerabilities in Apache Tomcat Native

Published: September 24, 2026

Security Bulletin ID SB2026092480
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 67% Low 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Out-of-bounds read (CVE-ID: CVE-2026-86243)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a buffer over-read in Apache Tomcat Native during TLS handshaking when processing a TLS handshake. A remote attacker can initiate a TLS handshake to cause a denial of service.


2) Insecure Default Initialization of Resource (CVE-ID: CVE-2026-86246)

CWE-ID: CWE-1188 - Insecure Default Initialization of Resource

CVSSv4: 0 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to weaken TLS connection security.

The vulnerability exists due to insecure default configuration in Apache Tomcat Native's OpenSSL option configuration when establishing TLS connections. A remote attacker can exploit the insecurely enabled OpenSSL options to weaken TLS connection security.


3) Race condition (CVE-ID: CVE-2026-86247)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 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]


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.


Remediation

Install update from vendor's website.