CVE intelligence and bounded remediation

CVE-2022-21716 — Twisted is an event-based framework for internet applications, supporting Python 3.6+

High CVSS 7.5

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.

Severity
High
CVSS
7.5 (3.1)
Published
2022-03-03
CISA KEV
Not currently listed
Ecosystem
python/pypi
Weaknesses
CWE-120, CWE-770

Affected products

  • twisted / twisted
  • 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

Showing 6 representative product identities from 7 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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