Related Vulnerabilities: CVE-2022-21716  

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 22.2.0, Twisted SSH client and server implement is able to accept an infinite amount of data for the peer's SSH version identifier. This ends up with a buffer using all the available memory. The attach is a simple as `nc -rv localhost 22 < /dev/zero`. A patch is available in version 22.2.0. There are currently no known workarounds.

Description

The MITRE CVE dictionary describes this issue as:

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 22.2.0, Twisted SSH client and server implement is able to accept an infinite amount of data for the peer's SSH version identifier. This ends up with a buffer using all the available memory. The attach is a simple as `nc -rv localhost 22 < /dev/zero`. A patch is available in version 22.2.0. There are currently no known workarounds.

Additional Information

  • Bugzilla 2060960: CVE-2022-21716 python-twisted: SSH client and server denial of service during SSH handshake
  • CWE-400: Uncontrolled Resource Consumption
  • FAQ: Frequently asked questions about CVE-2022-21716