CVE-2021-4189

 

Published at: - 24-08-2022 06:15

Last modified: - 29-08-2022 03:31

Total changes: - 2

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.

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

 

Verification logic

 

Reference

• https://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188e
• https://access.redhat.com/security/cve/CVE-2021-4189
• https://bugzilla.redhat.com/show_bug.cgi?id=2036020
• https://security-tracker.debian.org/tracker/CVE-2021-4189
• https://bugs.python.org/issue43285
• https://python-security.readthedocs.io/vuln/ftplib-pasv.html

 

Keywords

NVD

 

CVE-2021-4189

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures