CVE

CVE-2020-13935

7.5

CVSS

Description

The payload length in a WebSocket frame was not correctly validated in Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M1 to 9.0.36, 8.5.0 to 8.5.56 and 7.0.27 to 7.0.104. Invalid payload lengths could trigger an infinite loop. Multiple requests with invalid payload lengths could lead to a denial of service.

Attack Vector

Privileges Req.

User Interaction

apache tomcat

Updated Oct 12, 2026View on NVD →

S4E scanner

highNetwork Vulnerabilities~10 seconds

Apache Tomcat WebSocket Frame Payload Length Validation Denial of Service Scanner

Detects 'Denial of Service (DoS)' vulnerability in Apache Tomcat affects v. 10.0.0-M1 to 10.0.0-M6, 9.0.0.M1 to 9.0.36, 8.5.0 to 8.5.56, 7.0.27 to 7.0.104. This vulnerability can cause high CPU usage through malformed WebSocket frames.

Used 2.2k times · 3.4k assets checked · url

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