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GHSA-gw55-jm4h-x339

CriticalCVSS 9 / 10
Published May 8, 2020·Last modified Mar 13, 2026
Affected Components(0)

No affected components available

Description

The Java-WebSocket Client does not perform hostname verification.

  • This means that SSL certificates of other hosts are accepted as long as they are trusted. To exploit this vulnerability an attacker has to perform a man-in-the-middle (MITM) attack between a Java application using the Java-WebSocket Client and an WebSocket server it's connecting to.
  • TLS normally protects users and systems against MITM attacks, it cannot if certificates from other trusted hosts are accepted by the client.

For more information see: CWE-297: Improper Validation of Certificate with Host Mismatch - https://cwe.mitre.org/data/definitions/297.html

Important note

The OWASP Dependency-Check (https://jeremylong.github.io/DependencyCheck/index.html) may report that a dependency of your project is affected by this security vulnerability, but you don't use this lib. This is caused by the fuzzy search in the OWASP implementation. Check out this issue (https://github.com/TooTallNate/Java-WebSocket/issues/1019#issuecomment-628507934) for more information and a way to suppress the warning.

Risk Scores
Base Score
9.0

The vulnerability can be exploited over the network without needing physical access. It is difficult for an attacker to exploit this vulnerability and may require special conditions. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability. The vulnerability can affect other systems as well, not just the initial system. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a high impact on the availability of the system.

Threat Intelligence
8.2

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

EPSS
0.77%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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