What is CVE-2026-42498?

CVE-2026-42498 is a high-severity vulnerability in Apache Tomcat, classified under Information Disclosure. CVSS score: 7.3/10. Published 2026-05-12.

How severe is CVE-2026-42498?

High severity. CVSS v3 base score is 7.3 out of 10.

Information disclosure in Apache Tomcat

CVE-2026-42498

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 throug…

Vulnerability class: Information Disclosure

EPSS: 0.001 (15.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

Apache Tomcat
Apache Software Foundation Tomcat — versions 11.0.0-M1, 10.1.0-M1, 9.0.2

Weakness classification (CWE)

CWE-200 — Information Disclosure

References

security@apache.org (vendor-advisory, Mailing List, Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2026-42498?: CVE-2026-42498 is a high-severity vulnerability in Apache Tomcat, classified under Information Disclosure. CVSS score: 7.3/10. Published 2026-05-12.
How severe is CVE-2026-42498?: High severity. CVSS v3 base score is 7.3 out of 10.