SB20260721102 - Ubuntu update for tomcat8



SB20260721102 - Ubuntu update for tomcat8

Published: July 21, 2026

Security Bulletin ID SB20260721102
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 50% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 vulnerabilities.


1) Improper access control (CVE-ID: CVE-2026-43515)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/U:Green


The vulnerability allows a remote attacker to bypass security constraints.

The vulnerability exists due to improper access control in HTTP method constraint processing when evaluating multiple security constraints for the same extension pattern. A remote attacker can send a request using an improperly constrained HTTP method to bypass security constraints.


2) Cross-site scripting (CVE-ID: CVE-2026-50229)

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear


The vulnerability allows a remote attacker to execute cross-site scripting.

The vulnerability exists due to cross-site scripting in the number guess example when using wild card property mapping that exposes internal properties to clients. A remote attacker can supply crafted input that is reflected through exposed properties to execute cross-site scripting.

The issue is limited to the number guess example application.


3) Always-Incorrect Control Flow Implementation (CVE-ID: CVE-2026-53404)

CWE-ID: CWE-670 - Always-Incorrect Control Flow Implementation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to bypass rewrite conditions.

The vulnerability exists due to logic errors in RewriteValve when processing requests against OR-chained rewrite conditions. A remote attacker can send a request that matches the first OR condition to bypass rewrite conditions.

Exploitation requires a rule set that uses an OR chain followed by non-OR conditions.


4) Always-Incorrect Control Flow Implementation (CVE-ID: CVE-2026-55276)

CWE-ID: CWE-670 - Always-Incorrect Control Flow Implementation

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to obtain incomplete security configuration information.

The vulnerability exists due to logic errors in effective web.xml generation in the logged effective web.xml output when generating configuration logs. A local user can review the logged output to obtain incomplete security configuration information.

Special roles and empty authorization constraints are omitted from the logged effective web.xml.


Remediation

Install update from vendor's website.