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MEDIUM 5.3

CVE-2021-4189

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.

CVSS v3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS 1.1% percentile 77.8%

Affected tracked apps

Vulnerable CPE configurations

Vendor Product Platform Versions CPE 2.3 URI
python python Windows ≥3.6.0 <3.6.14 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python Windows ≥3.7.0 <3.7.11 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python Windows ≥3.8.0 <3.8.9 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python Windows ≥3.9.0 <3.9.3 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python Windows cpe:2.3:a:python:python:3.10.0:-:*:*:*:*:*:*
View on NVD ↗