CVE-2021-4189CWE-252

CVE-2021-4189

Medium · published August 24, 2022

CVSS v3.1
5.3
EPSS
3%
Percentile
88.8
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.03409 · 88.8th percentile
Weakness
CWE-252 · Unchecked Return Value
Published
2022-08-24T20:15Z
Affected products (10)
ProductVersionsFixed in
python/python≥ 3.6.0, < 3.6.143.6.14
python/python≥ 3.7.0, < 3.7.113.7.11
python/python≥ 3.8.0, < 3.8.93.8.9
python/python≥ 3.9.0, < 3.9.33.9.3
python/pythonall versions—
debian/debian_linuxall versions—
debian/debian_linuxall versions—
redhat/enterprise_linuxall versions—
redhat/software_collectionsall versions—
netapp/ontap_select_deploy_administration_utilityall versions—
References (20)
https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html · af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html · af854a3a-2127-422b-91ae-364da2661108https://python-security.readthedocs.io/vuln/ftplib-pasv.html · af854a3a-2127-422b-91ae-364da2661108https://security-tracker.debian.org/tracker/CVE-2021-4189 · af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20221104-0004/ · af854a3a-2127-422b-91ae-364da2661108https://cert-portal.siemens.com/productcert/html/ssa-398330.html · 0b142b55-0307-4c5a-b3c9-f314f3fb7c5ehttps://access.redhat.com/security/cve/CVE-2021-4189 · [email protected]https://bugs.python.org/issue43285 · [email protected]https://bugzilla.redhat.com/show_bug.cgi?id=2036020 · [email protected]https://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188e · [email protected]https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html · [email protected]https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html · [email protected]https://python-security.readthedocs.io/vuln/ftplib-pasv.html · [email protected]https://security-tracker.debian.org/tracker/CVE-2021-4189 · [email protected]https://security.netapp.com/advisory/ntap-20221104-0004/ · [email protected]https://access.redhat.com/security/cve/CVE-2021-4189 · af854a3a-2127-422b-91ae-364da2661108https://bugs.python.org/issue43285 · af854a3a-2127-422b-91ae-364da2661108https://bugzilla.redhat.com/show_bug.cgi?id=2036020 · af854a3a-2127-422b-91ae-364da2661108https://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188e · af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html · af854a3a-2127-422b-91ae-364da2661108
EPSS history
Timeline
  • 24 AUG 00:00Z
    A flaw was found in Python, specifically in the FTP (File Transfer Protocol) client library in PASV (passive) mode
    cvelistv5