RHSA-2021:4151MediumCVSS 7.8

Red Hat Security Advisory: python27:2.7 security update

Published
November 9, 2021
Last Modified
October 14, 2026

🔗 CVE IDs covered (8)

CVE-2021-23336 →CVE-2021-27291 →CVE-2021-28957 →CVE-2021-42771 →CVE-2020-27619 →CVE-2020-28493 →CVE-2021-20095 →CVE-2021-20270 →

📋 Description

CVE-2020-27619 — python: Unsafe use of eval() on data retrieved via HTTP in the test suite CVE-2020-28493 — python-jinja2: ReDoS vulnerability in the urlize filter CVE-2021-20095 — python-babel: Relative path traversal allows attacker to load arbitrary locale files and execute arbitrary code CVE-2021-20270 — python-pygments: Infinite loop in SML lexer may lead to DoS CVE-2021-23336 — python: Web cache poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a semicolon in query parameters CVE-2021-27291 — python-pygments: ReDoS in multiple lexers CVE-2021-28957 — python-lxml: Missing input sanitization for formaction HTML5 attributes may lead to XSS CVE-2021-42771 — python-babel: Relative path traversal allows attacker to load arbitrary locale files and execute arbitrary code

🎯 Affected products200

  • Red Hat Enterprise Linux AppStream (v. 8)
  • Cython-0:0.28.1-7.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • Cython-debugsource-0:0.28.1-7.module+el8.1.0+3111+de3f2d8e.aarch64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • Cython-debugsource-0:0.28.1-7.module+el8.1.0+3111+de3f2d8e.ppc64le (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • Cython-debugsource-0:0.28.1-7.module+el8.1.0+3111+de3f2d8e.s390x (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • Cython-debugsource-0:0.28.1-7.module+el8.1.0+3111+de3f2d8e.x86_64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • PyYAML-0:3.12-16.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • PyYAML-debugsource-0:3.12-16.module+el8.1.0+3111+de3f2d8e.aarch64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • PyYAML-debugsource-0:3.12-16.module+el8.1.0+3111+de3f2d8e.ppc64le (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • PyYAML-debugsource-0:3.12-16.module+el8.1.0+3111+de3f2d8e.s390x (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • PyYAML-debugsource-0:3.12-16.module+el8.1.0+3111+de3f2d8e.x86_64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • babel-0:2.5.1-10.module+el8.5.0+11014+88fc0d0b.noarch (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • babel-0:2.5.1-10.module+el8.5.0+11014+88fc0d0b.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • numpy-1:1.14.2-16.module+el8.4.0+9406+221a4565.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • numpy-debugsource-1:1.14.2-16.module+el8.4.0+9406+221a4565.aarch64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • numpy-debugsource-1:1.14.2-16.module+el8.4.0+9406+221a4565.ppc64le (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • numpy-debugsource-1:1.14.2-16.module+el8.4.0+9406+221a4565.s390x (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • numpy-debugsource-1:1.14.2-16.module+el8.4.0+9406+221a4565.x86_64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • pytest-0:3.4.2-13.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-PyMySQL-0:0.8.0-10.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-attrs-0:17.4.0-10.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-backports-0:1.0-16.module+el8.4.0+9193+f3daf6ef.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-backports-ssl_match_hostname-0:3.5.0.1-12.module+el8.4.0+9193+f3daf6ef.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-chardet-0:3.0.4-10.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-coverage-0:4.5.1-4.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-coverage-debugsource-0:4.5.1-4.module+el8.1.0+3111+de3f2d8e.aarch64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-coverage-debugsource-0:4.5.1-4.module+el8.1.0+3111+de3f2d8e.ppc64le (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-coverage-debugsource-0:4.5.1-4.module+el8.1.0+3111+de3f2d8e.s390x (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-coverage-debugsource-0:4.5.1-4.module+el8.1.0+3111+de3f2d8e.x86_64 (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • python-dns-0:1.15.0-10.module+el8.1.0+3111+de3f2d8e.src (python27:2.7) as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • +170 more not shown

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: In versions of Python shipped with Red Hat Enterprise Linux and Red Hat Software Collections, the flaw can be mitigated by not running the python tests with network resources enabled. By default, the tests are not run with network resources enabled. Ensure that `-u network` or `-uall` are not passed as options to `python -m test`. For more information on how these commands work, see [1]. 1. https://docs.python.org/3/library/test.html Workaround: If using the jinja2 library as a developer, this flaw can be mitigated by not using the vulnerable urlize() filter, and instead, using Markdown to format user content.

🔗 References (12)