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CVE-2020-13935

HighCVSS 7.5 / 10
Published Jul 14, 2020·Last modified Apr 16, 2026
Affected Components(0)

No affected components available

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.

Risk Scores
Base Score
7.5

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the availability of the system.

Threat Intelligence
7.1

Exploitation activity has been observed. Apply available patches or mitigations urgently.

EPSS
87.55%

The exploit probability is critical. The vulnerability is very likely to be exploited in the next 30 days.

Exploit
Proof of Concept

A proof of concept is available for this vulnerability (2 exploits found).

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