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Advisory severityMedium5.3Red Hat Linux

Medium [CVE-2021-4189] flaw was found in Python, specifically in the FTP (File Transfer Protocol) client library in PASV (passive) mode

This medium-severity Red Hat Linux advisory covers CVE-2021-4189 affecting Red Hat Enterprise Linux 8, Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS, Red Hat Enterprise Linux 6.

Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.

CVE-2021-4189 Source published Source updated

VulniPulse record published

CVE-2021-4189
Affected products & platforms
Red Hat LinuxRed Hat Enterprise Linux
Open source advisory

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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.

Red Hat severity: Moderate — CVSS 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N). Weakness: CWE-252.

Affected Red Hat products: Red Hat Enterprise Linux 8; Red Hat Software Collections for Red Hat Enterprise Linux 7; Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7. Red Hat lists Red Hat Enterprise Linux 8 as not affected.

Will not fix / out of support: Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7. Red Hat fixing advisory: RHSA-2022:1821, RHSA-2022:1986, RHSA-2021:3254, RHSA-2022:1663.

Affected products named by the advisory: Red Hat package: python3.

Affected versions

No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.

Official advisory · high-confidence parse· fetched 16 hours ago·verify at source

Fixed versions
  • python27:2.7-8060020220210185952.8cdc2268
  • python3-0:3.6.8-45.el8
  • rh-python38-babel-0:2.7.0-12.el7
  • rh-python38-python-0:3.8.11-2.el7
  • rh-python38-python-cryptography-0:2.8-5.el7
  • rh-python38-python-jinja2-0:2.10.3-6.el7
  • rh-python38-python-lxml-0:4.4.1-7.el7
  • rh-python38-python-pip-0:19.3.1-2.el7
  • rh-python38-python-urllib3-0:1.25.7-7.el7
  • python27-python-0:2.7.18-4.el7
  • RHSA-2022:1821
  • RHSA-2022:1986
  • RHSA-2021:3254
  • RHSA-2022:1663

Official advisory · high-confidence parse· fetched 16 hours ago·verify at source

Mitigation

Upgrade to a fixed release: python27:2.7-8060020220210185952.8cdc2268, python3-0:3.6.8-45.el8, rh-python38-babel-0:2.7.0-12.el7, rh-python38-python-0:3.8.11-2.el7, rh-python38-python-cryptography-0:2.8-5.el7, rh-python38-python-jinja2-0:2.10.3-6.el7. That is the remediation for this advisory.

The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.

Official advisory · high-confidence parse· fetched 16 hours ago·verify at source

Discussion(0)

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