HTTP Auth Header Leakage via WebSocket Auth in Apache Tomcat (V7-11)
CVE-2026-42498 Published on May 12, 2026
Apache Tomcat: WebSocket authentication header exposure
Exposure of HTTP Authentication Header to unexpected hosts during WebSocket authentication vulnerability in Apache Tomcat.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.2 through 9.0.117, from 8.5.24 through 8.5.100, from 7.0.83 through 7.0.109.
Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118, which fix the issue.
Vulnerability Analysis
CVE-2026-42498 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be low. considered to have a small impact on confidentiality and integrity and availability.
Weakness Type
What is an Information Disclosure Vulnerability?
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
CVE-2026-42498 has been classified to as an Information Disclosure vulnerability or weakness.
Products Associated with CVE-2026-42498
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Affected Versions
Apache Software Foundation Apache Tomcat:- Version 11.0.0-M1, <= 11.0.21 is affected.
- Version 10.1.0-M1, <= 10.1.54 is affected.
- Version 9.0.2, <= 9.0.117 is affected.
- Version 8.5.24, <= 8.5.100 is affected.
- Version 7.0.83, <= 7.0.109 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.