CVE-2022-21716

Name: CVE-2022-21716
Creator: NVD / NIST
Published: 2022-03-03T21:15:07.747+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 3.61%

Last modified Jun 17, 2026

CVE-2022-21716 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 3.61% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

3.61%

88.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Twisted	Twisted	>= 21.7.0, < 22.2.0
Debian	Debian Linux	9.0
Oracle	Http Server	12.2.1.3.0
Oracle	Http Server	12.2.1.4.0
Oracle	Zfs Storage Appliance Kit	8.8
Fedoraproject	Fedora	35
Fedoraproject	Fedora	36

References

https://github.com/twisted/twisted/commit/89c395ee794e85a9657b112c4351417850330ef9Patch, Third Party Advisory
https://github.com/twisted/twisted/releases/tag/twisted-22.2.0Release Notes, Third Party Advisory
https://github.com/twisted/twisted/security/advisories/GHSA-rv6r-3f5q-9rgxExploit, Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/03/msg00009.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7U6KYDTOLPICAVSR34G2WRYLFBD2YW5K/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GLKHA6WREIVAMBQD7KKWYHPHGGNKMAG6/
https://security.gentoo.org/glsa/202301-02Third Party Advisory
https://twistedmatrix.com/trac/ticket/10284Issue Tracking, Vendor Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
https://github.com/twisted/twisted/commit/89c395ee794e85a9657b112c4351417850330ef9Patch, Third Party Advisory
https://github.com/twisted/twisted/releases/tag/twisted-22.2.0Release Notes, Third Party Advisory
https://github.com/twisted/twisted/security/advisories/GHSA-rv6r-3f5q-9rgxExploit, Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/03/msg00009.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7U6KYDTOLPICAVSR34G2WRYLFBD2YW5K/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GLKHA6WREIVAMBQD7KKWYHPHGGNKMAG6/
https://security.gentoo.org/glsa/202301-02Third Party Advisory
https://twistedmatrix.com/trac/ticket/10284Issue Tracking, Vendor Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory

Timeline

Published: Mar 3, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-21716?

How severe is CVE-2022-21716?

CVE-2022-21716 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 3.61% probability of exploitation in the next 30 days.

How do I fix CVE-2022-21716?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2022-21716?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST