CVE-2021-4189

medium

Published 2022-05-10 · Modified 2022-05-10

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CVSS v3

—

CVSS v4 NEW

—

not yet in upstream

VIR risk

5.5

Description

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.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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OS impact

SUSE Affected 1 release

Version	Status	Fixed in
—	Affected	—

Debian Fixed 5 releases

Version	Status	Fixed in
trixie	Fixed	`7.3.5+dfsg-2`
sid	Fixed	`7.3.5+dfsg-2`
forky	Fixed	`7.3.5+dfsg-2`
bullseye	Fixed	`7.3.5+dfsg-2`
bookworm	Fixed	`7.3.5+dfsg-2`

Red Hat Fixed 1 release

Version	Status	Fixed in
8	Fixed	—

Rocky Linux Fixed 1 release

Version	Status	Fixed in
8	Fixed	—

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.