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Red Hat: CVE-2021-28957: CVE-2021-28957 python-lxml: Missing input sanitization for formaction HTML5 attributes may lead to XSS (Multiple Advisories)

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Red Hat: CVE-2021-28957: CVE-2021-28957 python-lxml: Missing input sanitization for formaction HTML5 attributes may lead to XSS (Multiple Advisories)

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
03/21/2021
Created
11/11/2021
Added
11/10/2021
Modified
11/26/2024

Description

An XSS vulnerability was discovered in python-lxml's clean module versions before 4.6.3. When disabling the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute allowing for JS to bypass the sanitizer. A remote attacker could exploit this flaw to run arbitrary JS code on users who interact with incorrectly sanitized HTML. This issue is patched in lxml 4.6.3.

Solution(s)

  • redhat-upgrade-babel
  • redhat-upgrade-cython-debugsource
  • redhat-upgrade-numpy-debugsource
  • redhat-upgrade-python-cffi-debugsource
  • redhat-upgrade-python-coverage-debugsource
  • redhat-upgrade-python-cryptography-debugsource
  • redhat-upgrade-python-lxml-debugsource
  • redhat-upgrade-python-markupsafe-debugsource
  • redhat-upgrade-python-nose-docs
  • redhat-upgrade-python-psutil-debugsource
  • redhat-upgrade-python-psycopg2-debuginfo
  • redhat-upgrade-python-psycopg2-debugsource
  • redhat-upgrade-python-psycopg2-doc
  • redhat-upgrade-python-pymongo-debuginfo
  • redhat-upgrade-python-pymongo-debugsource
  • redhat-upgrade-python-sqlalchemy-doc
  • redhat-upgrade-python2
  • redhat-upgrade-python2-attrs
  • redhat-upgrade-python2-babel
  • redhat-upgrade-python2-backports
  • redhat-upgrade-python2-backports-ssl_match_hostname
  • redhat-upgrade-python2-bson
  • redhat-upgrade-python2-bson-debuginfo
  • redhat-upgrade-python2-chardet
  • redhat-upgrade-python2-coverage
  • redhat-upgrade-python2-coverage-debuginfo
  • redhat-upgrade-python2-cython
  • redhat-upgrade-python2-cython-debuginfo
  • redhat-upgrade-python2-debug
  • redhat-upgrade-python2-debuginfo
  • redhat-upgrade-python2-debugsource
  • redhat-upgrade-python2-devel
  • redhat-upgrade-python2-dns
  • redhat-upgrade-python2-docs
  • redhat-upgrade-python2-docs-info
  • redhat-upgrade-python2-docutils
  • redhat-upgrade-python2-funcsigs
  • redhat-upgrade-python2-idna
  • redhat-upgrade-python2-ipaddress
  • redhat-upgrade-python2-jinja2
  • redhat-upgrade-python2-libs
  • redhat-upgrade-python2-lxml
  • redhat-upgrade-python2-lxml-debuginfo
  • redhat-upgrade-python2-markupsafe
  • redhat-upgrade-python2-mock
  • redhat-upgrade-python2-nose
  • redhat-upgrade-python2-numpy
  • redhat-upgrade-python2-numpy-debuginfo
  • redhat-upgrade-python2-numpy-doc
  • redhat-upgrade-python2-numpy-f2py
  • redhat-upgrade-python2-pip
  • redhat-upgrade-python2-pip-wheel
  • redhat-upgrade-python2-pluggy
  • redhat-upgrade-python2-psycopg2
  • redhat-upgrade-python2-psycopg2-debug
  • redhat-upgrade-python2-psycopg2-debug-debuginfo
  • redhat-upgrade-python2-psycopg2-debuginfo
  • redhat-upgrade-python2-psycopg2-tests
  • redhat-upgrade-python2-py
  • redhat-upgrade-python2-pygments
  • redhat-upgrade-python2-pymongo
  • redhat-upgrade-python2-pymongo-debuginfo
  • redhat-upgrade-python2-pymongo-gridfs
  • redhat-upgrade-python2-pymysql
  • redhat-upgrade-python2-pysocks
  • redhat-upgrade-python2-pytest
  • redhat-upgrade-python2-pytest-mock
  • redhat-upgrade-python2-pytz
  • redhat-upgrade-python2-pyyaml
  • redhat-upgrade-python2-pyyaml-debuginfo
  • redhat-upgrade-python2-requests
  • redhat-upgrade-python2-rpm-macros
  • redhat-upgrade-python2-scipy
  • redhat-upgrade-python2-scipy-debuginfo
  • redhat-upgrade-python2-setuptools
  • redhat-upgrade-python2-setuptools-wheel
  • redhat-upgrade-python2-setuptools_scm
  • redhat-upgrade-python2-six
  • redhat-upgrade-python2-sqlalchemy
  • redhat-upgrade-python2-test
  • redhat-upgrade-python2-tkinter
  • redhat-upgrade-python2-tools
  • redhat-upgrade-python2-urllib3
  • redhat-upgrade-python2-virtualenv
  • redhat-upgrade-python2-wheel
  • redhat-upgrade-python2-wheel-wheel
  • redhat-upgrade-python3-lxml
  • redhat-upgrade-python3-lxml-debuginfo
  • redhat-upgrade-python38
  • redhat-upgrade-python38-asn1crypto
  • redhat-upgrade-python38-atomicwrites
  • redhat-upgrade-python38-attrs
  • redhat-upgrade-python38-babel
  • redhat-upgrade-python38-cffi
  • redhat-upgrade-python38-cffi-debuginfo
  • redhat-upgrade-python38-chardet
  • redhat-upgrade-python38-cryptography
  • redhat-upgrade-python38-cryptography-debuginfo
  • redhat-upgrade-python38-cython
  • redhat-upgrade-python38-cython-debuginfo
  • redhat-upgrade-python38-debug
  • redhat-upgrade-python38-debuginfo
  • redhat-upgrade-python38-debugsource
  • redhat-upgrade-python38-devel
  • redhat-upgrade-python38-idle
  • redhat-upgrade-python38-idna
  • redhat-upgrade-python38-jinja2
  • redhat-upgrade-python38-libs
  • redhat-upgrade-python38-lxml
  • redhat-upgrade-python38-lxml-debuginfo
  • redhat-upgrade-python38-markupsafe
  • redhat-upgrade-python38-markupsafe-debuginfo
  • redhat-upgrade-python38-mod_wsgi
  • redhat-upgrade-python38-more-itertools
  • redhat-upgrade-python38-numpy
  • redhat-upgrade-python38-numpy-debuginfo
  • redhat-upgrade-python38-numpy-doc
  • redhat-upgrade-python38-numpy-f2py
  • redhat-upgrade-python38-packaging
  • redhat-upgrade-python38-pip
  • redhat-upgrade-python38-pip-wheel
  • redhat-upgrade-python38-pluggy
  • redhat-upgrade-python38-ply
  • redhat-upgrade-python38-psutil
  • redhat-upgrade-python38-psutil-debuginfo
  • redhat-upgrade-python38-psycopg2
  • redhat-upgrade-python38-psycopg2-debuginfo
  • redhat-upgrade-python38-psycopg2-doc
  • redhat-upgrade-python38-psycopg2-tests
  • redhat-upgrade-python38-py
  • redhat-upgrade-python38-pycparser
  • redhat-upgrade-python38-pymysql
  • redhat-upgrade-python38-pyparsing
  • redhat-upgrade-python38-pysocks
  • redhat-upgrade-python38-pytest
  • redhat-upgrade-python38-pytz
  • redhat-upgrade-python38-pyyaml
  • redhat-upgrade-python38-pyyaml-debuginfo
  • redhat-upgrade-python38-requests
  • redhat-upgrade-python38-rpm-macros
  • redhat-upgrade-python38-scipy
  • redhat-upgrade-python38-scipy-debuginfo
  • redhat-upgrade-python38-setuptools
  • redhat-upgrade-python38-setuptools-wheel
  • redhat-upgrade-python38-six
  • redhat-upgrade-python38-test
  • redhat-upgrade-python38-tkinter
  • redhat-upgrade-python38-urllib3
  • redhat-upgrade-python38-wcwidth
  • redhat-upgrade-python38-wheel
  • redhat-upgrade-python38-wheel-wheel
  • redhat-upgrade-python39
  • redhat-upgrade-python39-attrs
  • redhat-upgrade-python39-cffi
  • redhat-upgrade-python39-cffi-debuginfo
  • redhat-upgrade-python39-chardet
  • redhat-upgrade-python39-cryptography
  • redhat-upgrade-python39-cryptography-debuginfo
  • redhat-upgrade-python39-cython
  • redhat-upgrade-python39-cython-debuginfo
  • redhat-upgrade-python39-debug
  • redhat-upgrade-python39-debuginfo
  • redhat-upgrade-python39-debugsource
  • redhat-upgrade-python39-devel
  • redhat-upgrade-python39-idle
  • redhat-upgrade-python39-idna
  • redhat-upgrade-python39-iniconfig
  • redhat-upgrade-python39-libs
  • redhat-upgrade-python39-lxml
  • redhat-upgrade-python39-lxml-debuginfo
  • redhat-upgrade-python39-mod_wsgi
  • redhat-upgrade-python39-more-itertools
  • redhat-upgrade-python39-numpy
  • redhat-upgrade-python39-numpy-debuginfo
  • redhat-upgrade-python39-numpy-doc
  • redhat-upgrade-python39-numpy-f2py
  • redhat-upgrade-python39-packaging
  • redhat-upgrade-python39-pip
  • redhat-upgrade-python39-pip-wheel
  • redhat-upgrade-python39-pluggy
  • redhat-upgrade-python39-ply
  • redhat-upgrade-python39-psutil
  • redhat-upgrade-python39-psutil-debuginfo
  • redhat-upgrade-python39-psycopg2
  • redhat-upgrade-python39-psycopg2-debuginfo
  • redhat-upgrade-python39-psycopg2-doc
  • redhat-upgrade-python39-psycopg2-tests
  • redhat-upgrade-python39-py
  • redhat-upgrade-python39-pybind11
  • redhat-upgrade-python39-pybind11-devel
  • redhat-upgrade-python39-pycparser
  • redhat-upgrade-python39-pymysql
  • redhat-upgrade-python39-pyparsing
  • redhat-upgrade-python39-pysocks
  • redhat-upgrade-python39-pytest
  • redhat-upgrade-python39-pyyaml
  • redhat-upgrade-python39-pyyaml-debuginfo
  • redhat-upgrade-python39-requests
  • redhat-upgrade-python39-rpm-macros
  • redhat-upgrade-python39-scipy
  • redhat-upgrade-python39-scipy-debuginfo
  • redhat-upgrade-python39-setuptools
  • redhat-upgrade-python39-setuptools-wheel
  • redhat-upgrade-python39-six
  • redhat-upgrade-python39-test
  • redhat-upgrade-python39-tkinter
  • redhat-upgrade-python39-toml
  • redhat-upgrade-python39-urllib3
  • redhat-upgrade-python39-wcwidth
  • redhat-upgrade-python39-wheel
  • redhat-upgrade-python39-wheel-wheel
  • redhat-upgrade-pyyaml-debugsource
  • redhat-upgrade-scipy-debugsource

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