Vulnerabilities
Misconfiguration
Compliance
CVE Vulnerabilities

CVE-2021-43818

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Published: Dec 13, 2021 | Modified: Nov 21, 2024
CVSS 3.x
7.1
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
CVSS 2.x
6.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
8.8 MODERATE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-43818
CWEhttps://cwe.mitre.org/data/definitions/74.html

lxml is a library for processing XML and HTML in the Python language. Prior to version 4.6.5, the HTML Cleaner in lxml.html lets certain crafted script content pass through, as well as script content in SVG files embedded using data URIs. Users that employ the HTML cleaner in a security relevant context should upgrade to lxml 4.6.5 to receive a patch. There are no known workarounds available.

Weakness

The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

Affected Software

NameVendorStart VersionEnd Version
LxmlLxml*4.6.5 (excluding)
Red Hat Enterprise Linux 8RedHatpython39:3.9-8060020220118220913.d3811607*
Red Hat Enterprise Linux 8RedHatpython38:3.8-8060020220120164031.5294be16*
Red Hat Enterprise Linux 8RedHatpython27:2.7-8060020220210185952.8cdc2268*
Red Hat Enterprise Linux 8RedHatpython-lxml-0:4.2.3-4.el8*
Red Hat Satellite 6.11 for RHEL 8RedHatpython-lxml-0:4.7.1-1.el8pc*
Red Hat Satellite 6.11 for RHEL 8RedHatpython-lxml-0:4.7.1-1.el8pc*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-python-lxml-0:4.4.1-8.el7*
LxmlUbuntubionic*
LxmlUbuntudevel*
LxmlUbuntuesm-infra-legacy/trusty*
LxmlUbuntuesm-infra/bionic*
LxmlUbuntuesm-infra/focal*
LxmlUbuntuesm-infra/xenial*
LxmlUbuntufocal*
LxmlUbuntuhirsute*
LxmlUbuntuimpish*
LxmlUbuntujammy*
LxmlUbuntutrusty*
LxmlUbuntutrusty/esm*
LxmlUbuntuxenial*

Potential Mitigations

References

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