High severity · published Dec 13, 2021
CVE-2021-43818
lxml is a library for processing XML and HTML in the Python language
7.1
CVSS
2.7%
EPSS
No
On KEV
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
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)2.7% · higher than 86% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
Communications Cloud Native Core Binding Support Function · Oracle
22.1.3 · source: NVD
CC
Communications Cloud Native Core Network Exposure Function · Oracle
22.1.1 · source: NVD
CC
Communications Cloud Native Core Policy · Oracle
22.2.0 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
FE
Fedora · Fedoraproject
34; 35 · source: NVD
HS
Hci Storage Node Firmware · Netapp
All versions, or not specified · source: NVD
HS
Http Server · Oracle
12.2.1.3.0; 12.2.1.4.0 · source: NVD
LX
Lxml · Lxml
before 4.6.5 · source: NVD
SO
Solidfire · Netapp
All versions, or not specified · source: NVD
SE
Solidfire Enterprise Sds · Netapp
All versions, or not specified · source: NVD
ZS
Zfs Storage Appliance Kit · Oracle
8.8 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43818
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43818
Patch
https://github.com/lxml/lxml/commit/12fa9669007180a7bb87d990c375cf91ca5b664a
Patch
https://github.com/lxml/lxml/commit/a3eacbc0dcf1de1c822ec29fb7d090a4b1712a9c#diff-59130575b4fb2932c957db2922977d7d89afb0b2085357db1a14615a2fcad776
Patch
https://github.com/lxml/lxml/commit/f2330237440df7e8f39c3ad1b1aa8852be3b27c0
Third Party Advisory
https://github.com/lxml/lxml/security/advisories/GHSA-55x5-fj6c-h6m8
Mailing List
https://lists.debian.org/debian-lts-announce/2021/12/msg00037.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TUIS2KE3HZ2AAQKXFLTJFZPP2IFHJTC7/
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