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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2021-4189 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://access.redhat.com/security/cve/CVE-2021-4189 Third Party Advisory 
https://access.redhat.com/security/cve/CVE-2021-4189 Third Party Advisory 
https://bugs.python.org/issue43285 Patch  Vendor Advisory 
https://bugs.python.org/issue43285 Patch  Vendor Advisory 
https://bugzilla.redhat.com/show_bug.cgi?id=2036020 Issue Tracking  Patch  Third Party Advisory 
https://bugzilla.redhat.com/show_bug.cgi?id=2036020 Issue Tracking  Patch  Third Party Advisory 
https://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188e Patch  Third Party Advisory 
https://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188e Patch  Third Party Advisory 
https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
https://python-security.readthedocs.io/vuln/ftplib-pasv.html Patch  Third Party Advisory 
https://python-security.readthedocs.io/vuln/ftplib-pasv.html Patch  Third Party Advisory 
https://security-tracker.debian.org/tracker/CVE-2021-4189 Third Party Advisory 
https://security-tracker.debian.org/tracker/CVE-2021-4189 Third Party Advisory 
https://security.netapp.com/advisory/ntap-20221104-0004/ Third Party Advisory 
https://security.netapp.com/advisory/ntap-20221104-0004/ Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-252 Unchecked Return Value cwe source acceptance level NIST  

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Change History

7 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-4189
NVD Published Date:
08/24/2022
NVD Last Modified:
11/21/2024
Source:
Red Hat, Inc.