Information disclosure in Apache Tomcat - CVE-2026-42498

 

Information disclosure in Apache Tomcat - CVE-2026-42498

Published: May 12, 2026


Vulnerability identifier: #VU131181
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-42498
CWE-ID: CWE-200
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote user to disclose authentication headers to a redirect target host.

The vulnerability exists due to exposure of sensitive information in Tomcat's WebSocket client when following a redirected WebSocket request after authentication. A remote user can trigger a redirect after authentication to disclose authentication headers to a redirect target host.

The issue occurs only if a WebSocket request is redirected after authentication.


Affected software

Apache Tomcat
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP6
Debian Linux
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 12
Red Hat Enterprise Linux Server - TUS
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Web and Scripting Module
openSUSE Leap
Ubuntu
openEuler
Anolis OS
Db2 Developer Extension
Storage Defender Copy Data Management
Maximo Application Suite - Monitor Component
CICS Transaction Gateway Desktop Edition
CICS Transaction Gateway for Multiplatforms
ApplinX
Dell Wyse Management Suite
IBM Watson Speech Services Cartridge for IBM Cloud Pak for Data
IBM Watson Discovery for IBM Cloud Pak for Data
Jira Service Management Data Center
Jira Service Management Server
Confluence Data Center
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
tomcat10 (Ubuntu package)
tomcat-webapps
tomcat-help
tomcat-jsvc
tomcat-lib
tomcat-jsp-2.3-api
tomcat-docs-webapp
tomcat-doc
tomcat-servlet-4.0-api
tomcat-el-3.0-api
tomcat-admin-webapps
tomcat
tomcat-servlet-4_0-api
tomcat-javadoc
tomcat-jsp-2_3-api
tomcat-el-3_0-api
tomcat (Red Hat package)
tomcat9 (Red Hat package)
tomcat10 (Debian package)
tomcat10-lib
tomcat10-servlet-6_0-api
tomcat10-admin-webapps
tomcat10
tomcat10-webapps
tomcat10-el-5_0-api
tomcat10-jsp-3_1-api
tomcat11 (Ubuntu package)
tomcat11 (Debian package)
tomcat11-admin-webapps
tomcat11
tomcat11-servlet-6_1-api
tomcat11-doc
tomcat11-jsvc
tomcat11-docs-webapp
tomcat11-webapps
tomcat11-lib
tomcat11-jsp-4_0-api
tomcat11-embed
tomcat11-el-6_0-api

How to mitigate CVE-2026-42498

Install security update from vendor's website.

Apache Tomcat - addressed in versions 9.0.118, 10.1.55, 11.0.22
Db2 Developer Extension - update to 1.1.2
Storage Defender Copy Data Management - update to 2.3.1.0
IBM Watson Speech Services Cartridge for IBM Cloud Pak for Data - update to 5.4.0 Patch 3
IBM Watson Discovery for IBM Cloud Pak for Data - update to 5.3.2
Jira Service Management Data Center - addressed in versions 10.3.22, 11.3.7
Jira Service Management Server - addressed in versions 10.3.22, 11.3.7
Confluence Data Center - addressed in versions 9.2.21, 10.2.13
Maximo Application Suite - Monitor Component - addressed in versions 9.0.22, 9.1.12
tomcat10 (Ubuntu package) - addressed in versions 9.0.16-3ubuntu0.18.04.2+esm8, 9.0.31-1ubuntu0.9+esm3, 9.0.58-1ubuntu0.2+esm4, 9.0.70-2ubuntu0.1+esm3, 9.0.95-1ubuntu1.1, 9.0.115-1ubuntu0.1, 10.1.16-1ubuntu0.1~esm4, 10.1.40-1ubuntu1.25.10.1, 10.1.40-1ubuntu1.26.04.1
tomcat-webapps - update to 9.0.118-1
tomcat-help - update to 9.0.118-1
tomcat-jsvc - update to 9.0.118-1
tomcat-lib - update to 9.0.118-1
tomcat-jsp-2.3-api - update to 9.0.118-1
tomcat-docs-webapp - update to 9.0.118-1
tomcat-doc - update to 9.0.118-1
tomcat-servlet-4.0-api - update to 9.0.118-1
tomcat-el-3.0-api - update to 9.0.118-1
tomcat-admin-webapps - update to 9.0.118-1
tomcat - update to 9.0.118-1
tomcat - update to 9.0.118-1
tomcat-webapps - addressed in versions 9.0.118-3.166.1, 9.0.118-150200.108.1
tomcat-servlet-4_0-api - addressed in versions 9.0.118-3.166.1, 9.0.118-150200.108.1
tomcat-admin-webapps - addressed in versions 9.0.118-3.166.1, 9.0.118-150200.108.1
tomcat-lib - addressed in versions 9.0.118-3.166.1, 9.0.118-150200.108.1
tomcat - addressed in versions 9.0.118-3.166.1, 9.0.118-150200.108.1
tomcat-javadoc - update to 9.0.118-3.166.1
tomcat-docs-webapp - update to 9.0.118-3.166.1
tomcat-jsp-2_3-api - addressed in versions 9.0.118-3.166.1, 9.0.118-150200.108.1
tomcat-el-3_0-api - addressed in versions 9.0.118-3.166.1, 9.0.118-150200.108.1
tomcat (Red Hat package) - addressed in versions 9.0.120-1.el8_8, 9.0.120-1.el9_2, 9.0.120-1.el9_4, 9.0.120-2.el9_8, 10.1.49-1.el10_0, 10.1.49-4.el10_2
tomcat9 (Red Hat package) - update to 9.0.120-1.el10_2
tomcat10 (Debian package) - addressed in versions 10.1.55-1~deb12u1, 10.1.55-1~deb13u1
tomcat10-lib - update to 10.1.55-150200.5.67.1
tomcat10-servlet-6_0-api - update to 10.1.55-150200.5.67.1
tomcat10-admin-webapps - update to 10.1.55-150200.5.67.1
tomcat10 - update to 10.1.55-150200.5.67.1
tomcat10-webapps - update to 10.1.55-150200.5.67.1
tomcat10-el-5_0-api - update to 10.1.55-150200.5.67.1
tomcat10-jsp-3_1-api - update to 10.1.55-150200.5.67.1
tomcat11 (Ubuntu package) - update to 11.0.18-1ubuntu0.1~esm1
tomcat11 (Debian package) - update to 11.0.22-1~deb13u1
tomcat11-admin-webapps - update to 11.0.22-150600.13.21.1
tomcat11 - update to 11.0.22-150600.13.21.1
tomcat11-servlet-6_1-api - update to 11.0.22-150600.13.21.1
tomcat11-doc - update to 11.0.22-150600.13.21.1
tomcat11-jsvc - update to 11.0.22-150600.13.21.1
tomcat11-docs-webapp - update to 11.0.22-150600.13.21.1
tomcat11-webapps - update to 11.0.22-150600.13.21.1
tomcat11-lib - update to 11.0.22-150600.13.21.1
tomcat11-jsp-4_0-api - update to 11.0.22-150600.13.21.1
tomcat11-embed - update to 11.0.22-150600.13.21.1
tomcat11-el-6_0-api - update to 11.0.22-150600.13.21.1
Dell Wyse Management Suite - update to 2605 HF1

External References

Related Security Bulletins