RHSA-2021:4158: Moderate: python-lxml security update

Published Nov 9, 2021
·
Updated

lxml is an XML processing library providing access to libxml2 and libxslt libraries using the Python ElementTree API. Security Fix(es): python-lxml: Missing input sanitization for formaction HTML5 attributes may lead to XSS (CVE-2021-28957) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.Additional Changes:For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.5 Release Notes linked from the References section.

Affected Software

13 affected componentsFixes available
redhat/python-lxml<4.2.3-3.el8
4.2.3-3.el8
redhat/python-lxml-debugsource<4.2.3-3.el8
4.2.3-3.el8
redhat/python3-lxml<4.2.3-3.el8
4.2.3-3.el8
redhat/python3-lxml-debuginfo<4.2.3-3.el8
4.2.3-3.el8
redhat/python-lxml-debugsource<4.2.3-3.el8
4.2.3-3.el8
redhat/python3-lxml<4.2.3-3.el8
4.2.3-3.el8
redhat/python3-lxml-debuginfo<4.2.3-3.el8
4.2.3-3.el8
redhat/python-lxml-debugsource<4.2.3-3.el8
4.2.3-3.el8
redhat/python3-lxml<4.2.3-3.el8
4.2.3-3.el8
redhat/python3-lxml-debuginfo<4.2.3-3.el8
4.2.3-3.el8
redhat/python-lxml-debugsource<4.2.3-3.el8.aa
4.2.3-3.el8.aa
redhat/python3-lxml<4.2.3-3.el8.aa
4.2.3-3.el8.aa
redhat/python3-lxml-debuginfo<4.2.3-3.el8.aa
4.2.3-3.el8.aa

Remediation

Event History

May 17, 2026
Advisory Published
via Red Hat·06:53 PM
Data Sourced
via Red Hat·06:53 PM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of RHSA-2021:4158?

The severity of RHSA-2021:4158 is classified as moderate.

2

How do I fix RHSA-2021:4158?

To fix RHSA-2021:4158, update the python-lxml package to version 4.2.3-3.el8 or later.

3

What type of vulnerability is addressed in RHSA-2021:4158?

RHSA-2021:4158 addresses a missing input sanitization vulnerability that could lead to XSS attacks.

4

Which software versions are affected by RHSA-2021:4158?

The affected software versions include python-lxml prior to 4.2.3-3.el8, including its debug and debug source packages.

5

What package is recommended to mitigate the issue in RHSA-2021:4158?

The recommended package to mitigate the issue in RHSA-2021:4158 is python-lxml version 4.2.3-3.el8.

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