CVE-2021-4189

Published: 31 December 2021

A flaw was found in Python, specifically in the FTP (File Transfer Protocol) client library in PASV (passive) mode. The issue is how the FTP client trusts the host from the PASV response by default. This flaw allows an attacker to set up a malicious FTP server that can trick FTP clients into connecting back to a given IP address and port. This vulnerability could lead to FTP client scanning ports, which otherwise would not have been possible.

Priority

Cvss 3 Severity Score

5.3

Score breakdown

Status

Package	Release	Status
python2.7 Launchpad, Ubuntu, Debian	bionic	Released (2.7.17-1~18.04ubuntu1.7)
	focal	Needed
	hirsute	Ignored (reached end-of-life)
	impish	Ignored (reached end-of-life)
	jammy	Needed
	kinetic	Needed
	lunar	Does not exist
	trusty	Released (2.7.6-8ubuntu0.6+esm12)
	upstream	Needs triage
	xenial	Released (2.7.12-1ubuntu0~16.04.18+esm1)
python3.10 Launchpad, Ubuntu, Debian	bionic	Does not exist
	focal	Does not exist
	hirsute	Ignored (reached end-of-life)
	impish	Not vulnerable (3.10.0-2)
	jammy	Not vulnerable (3.10.0-2)
	kinetic	Not vulnerable (3.10.0-2)
	lunar	Does not exist
	trusty	Does not exist
	upstream	Needs triage
	xenial	Does not exist
	Patches: upstream: https://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188e
python3.4 Launchpad, Ubuntu, Debian	bionic	Does not exist
	focal	Does not exist
	hirsute	Does not exist
	impish	Does not exist
	jammy	Does not exist
	kinetic	Does not exist
	lunar	Does not exist
	trusty	Released (3.4.3-1ubuntu1~14.04.7+esm12)
	upstream	Needed
	xenial	Does not exist
python3.5 Launchpad, Ubuntu, Debian	bionic	Does not exist
	focal	Does not exist
	hirsute	Does not exist
	impish	Does not exist
	jammy	Does not exist
	kinetic	Does not exist
	lunar	Does not exist
	trusty	Needed
	upstream	Needed
	xenial	Released (3.5.2-2ubuntu0~16.04.13+esm2)
python3.6 Launchpad, Ubuntu, Debian	bionic	Released (3.6.9-1~18.04ubuntu1.7)
	focal	Does not exist
	hirsute	Does not exist
	impish	Does not exist
	jammy	Does not exist
	kinetic	Does not exist
	lunar	Does not exist
	trusty	Does not exist
	upstream	Released (3.6.14)
	xenial	Does not exist
	Patches: upstream: https://github.com/python/cpython/commit/4134f154ae2f621f25c5d698cc0f1748035a1b88
python3.7 Launchpad, Ubuntu, Debian	bionic	Needed
	focal	Does not exist
	hirsute	Does not exist
	impish	Does not exist
	jammy	Does not exist
	kinetic	Does not exist
	lunar	Does not exist
	trusty	Does not exist
	upstream	Released (3.7.11)
	xenial	Does not exist
	Patches: upstream: https://github.com/python/cpython/commit/79373951b3eab585d42e0f0ab83718cbe1d0ee33
python3.8 Launchpad, Ubuntu, Debian	bionic	Needed
	focal	Not vulnerable
	hirsute	Does not exist
	impish	Does not exist
	jammy	Does not exist
	kinetic	Does not exist
	lunar	Does not exist
	trusty	Does not exist
	upstream	Needed
	xenial	Does not exist
python3.9 Launchpad, Ubuntu, Debian	bionic	Does not exist
	focal	Not vulnerable (3.9.5-3ubuntu0~20.04.1)
	hirsute	Ignored (reached end-of-life)
	impish	Not vulnerable (3.9.7-2build1)
	jammy	Does not exist
	kinetic	Does not exist
	lunar	Does not exist
	trusty	Does not exist
	upstream	Released (3.9.7-1)
	xenial	Does not exist
	Patches: upstream: https://github.com/python/cpython/commit/7dcb4baa4f0fde3aef5122a8e9f6a41853ec9335

Severity score breakdown

Parameter	Value
Base score	5.3
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	Low
Integrity impact	None
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

References

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