Apache Tomcat: WebSocket DoS with incomplete closing handshake
At a glance
Severity
MEDIUM 6.3
EPSS
EPSS 2.31 % · percentile 83 (2026-10-28)
State
PUBLISHED
Published
Updated
Assigner
apache
NVD status
Modified
Description
Denial of Service via incomplete cleanup vulnerability in Apache Tomcat. It was possible for WebSocket clients to keep WebSocket connections open leading to increased resource consumption.This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.0-M16, from 10.1.0-M1 through 10.1.18, from 9.0.0-M1 through 9.0.85, from 8.5.0 through 8.5.98.
Older, EOL versions may also be affected.
Users are recommended to upgrade to version 11.0.0-M17, 10.1.19, 9.0.86 or 8.5.99 which fix the issue.