Most recent entries from all

CVE-2022-21716 — Buffer Overflow in Twisted

2026-09-29T02:59:27.554958+00:00

Affected: twisted

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.

GHSA-rv6r-3f5q-9rgx — Twisted SSH client and server deny of service during SSH handshake.

2026-09-29T02:59:27.555175+00:00

Affected: PyPI: twisted

### Impact

The Twisted SSH client and server implementation naively accepted an infinite amount of data for the peer's SSH version identifier.

A malicious peer can trivially craft a request that uses all available memory and crash the server, resulting in denial of service. The attack is as simple as `nc -rv localhost 22 < /dev/zero`.

### Patches

The issue was fix in GitHub commit https://github.com/twisted/twisted/commit/98387b39e9f0b21462f6abc7a1325dc370fcdeb1

A fix is available in Twisted 22.2.0.

### Workarounds

* Limit access to the SSH server only to trusted source IP addresses. * Connect over SSH only to trusted destination IP addresses.

### References

Reported at https://twistedmatrix.com/trac/ticket/10284 Discussions at https://github.com/twisted/twisted/security/advisories/GHSA-rv6r-3f5q-9rgx

### For more information

Found by vin01

PYSEC-2022-160

2026-09-29T02:59:27.555254+00:00

Affected: PyPI: twisted