🛡️ UBUNTU-CVE-2021-4189
⚪ Unknown ✅ No Known Exploit OSV
N/A
CVSS Score
0 Low4 Medium7 High9 Critical10

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.

Details

Severity Unknown
CVSS Score N/A
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2021-12-31
Updated 2026-06-15
Modified 2026-04-22
Fix URL N/A

Affected Packages

Software From version Fixed in
python2.7 2.7.18-13ubuntu1.1+esm2
python3.4 3.4.3-1ubuntu1~14.04.7+esm12
python3.5 3.5.2-2ubuntu0~16.04.13+esm2
python3.6 3.6.9-1~18.04ubuntu1.7
python3.7 3.7.5-2ubuntu1~18.04.2+esm3
python3.8 3.8.0-3ubuntu1~18.04.2+esm2

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