CVE-2021-4189 (GCVE-0-2021-4189)

Vulnerability from cvelistv5 – Published: 2022-08-24 00:00 – Updated: 2025-12-17 21:36
VLAI?
Summary
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.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE
  • Not-Known
Assigner
References
Impacted products
Vendor Product Version
n/a python Affected: Fixed in python 3.6.14, python 3.7.11, python 3.8.9, python 3.9.3, python 3.10.0
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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