FKIE_CVE-2021-4189

Vulnerability from fkie_nvd - Published: 2022-08-24 16:15 - Updated: 2025-12-17 22:15
Severity ?
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Summary
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.
References
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2021-4189Third Party Advisory
secalert@redhat.comhttps://bugs.python.org/issue43285Patch, Vendor Advisory
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2036020Issue Tracking, Patch, Third Party Advisory
secalert@redhat.comhttps://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188ePatch, Third Party Advisory
secalert@redhat.comhttps://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
secalert@redhat.comhttps://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
secalert@redhat.comhttps://python-security.readthedocs.io/vuln/ftplib-pasv.htmlPatch, Third Party Advisory
secalert@redhat.comhttps://security-tracker.debian.org/tracker/CVE-2021-4189Third Party Advisory
secalert@redhat.comhttps://security.netapp.com/advisory/ntap-20221104-0004/Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://access.redhat.com/security/cve/CVE-2021-4189Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://bugs.python.org/issue43285Patch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://bugzilla.redhat.com/show_bug.cgi?id=2036020Issue Tracking, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/python/cpython/commit/0ab152c6b5d95caa2dc1a30fa96e10258b5f188ePatch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
af854a3a-2127-422b-91ae-364da2661108https://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.htmlPatch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://security-tracker.debian.org/tracker/CVE-2021-4189Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20221104-0004/Third Party Advisory
Impacted products
Vendor Product Version
python python *
python python *
python python *
python python *
python python 3.10.0
debian debian_linux 10.0
debian debian_linux 11.0
redhat software_collections -
redhat enterprise_linux 8.0
netapp ontap_select_deploy_administration_utility -
To clipboard 

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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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