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CVE-2021-43818

HTML Cleaner allows crafted and SVG embedded scripts to pass through

Published: Dec 13, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-74
NVD MITRE
8.2CVSSHIGH
EPSS Score
2.5%
Top 17.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:RS:CC:LI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:CScope
Changed
Impact
C:LConfidentiality
Low
I:HIntegrity
High
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-74CWE-79

Affected Products

lxmllxml
Library
OSS Libraries / generic-library
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
debian linuxdebian
On-premOS
Operating Systems / linux-distro
solidfirenetappHardware Firmware
solidfire enterprise sdsnetappHardware Firmware
lxmloss-projectOSS Librariesaka lxml/lxml
fedoraprojectoss-projectUSOperating Systemsaka fedora project
debianoss-projectGBOperating Systemsaka debian gnu/linux
netappcommercialUSHardware Firmware
and 24 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

3 techniques
Execution
Initial Access
View detailed technique mapping

References

https://github.com/lxml/lxml/commit/12fa9669007180a7bb87d990c375cf91ca5b664a
github.com
https://github.com/lxml/lxml/commit/a3eacbc0dcf1de1c822ec29fb7d090a4b1712a9c#diff-59130575b4fb2932c957db2922977d7d89afb0b2085357db1a14615a2fcad776
github.com
https://github.com/lxml/lxml/commit/f2330237440df7e8f39c3ad1b1aa8852be3b27c0
github.com
and 35 more references View all →

Timeline

Published
Dec 13, 2021
Last Updated
Nov 21, 2024

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