GHSA-pgww-xf46-h92r

lxml vulnerable to Cross-site Scripting

At a glance

Published: 2021-01-07 21:54 UTC
Updated: 2025-12-20 05:25 UTC
CVE: CVE-2020-27783
Aliases: PYSEC-2020-62
CVSS_V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS_V4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

Description

A XSS vulnerability was discovered in python-lxml's clean module. The module's parser didn't properly imitate browsers, which caused different behaviors between the sanitizer and the user's page. A remote attacker could exploit this flaw to run arbitrary HTML/JS code.

Affected packages

Package	Versions
PyPI · lxml	introduced 0, fixed 4.6.2

References

https://nvd.nist.gov/vuln/detail/CVE-2020-27783 ADVISORY
https://github.com/lxml/lxml/commit/a105ab8dc262ec6735977c25c13f0bdfcdec72a7 WEB
https://www.oracle.com//security-alerts/cpujul2021.html WEB
https://www.debian.org/security/2020/dsa-4810 WEB
https://snyk.io/vuln/SNYK-PYTHON-LXML-1047473 WEB
https://security.netapp.com/advisory/ntap-20210521-0003 WEB
https://pypi.org/project/lxml WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TMHVKRUT22LVWNL3TB7HPSDHJT74Q3JK WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JKG67GPGTV23KADT4D4GK4RMHSO4CIQL WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TMHVKRUT22LVWNL3TB7HPSDHJT74Q3JK WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JKG67GPGTV23KADT4D4GK4RMHSO4CIQL WEB
https://lists.debian.org/debian-lts-announce/2020/12/msg00028.html WEB
https://github.com/pypa/advisory-database/tree/main/vulns/lxml/PYSEC-2020-62.yaml WEB
https://github.com/lxml/lxml WEB
https://github.com/advisories/GHSA-pgww-xf46-h92r ADVISORY
https://bugzilla.redhat.com/show_bug.cgi?id=1901633 WEB
https://advisory.checkmarx.net/advisory/CX-2020-4286 WEB

Sources

Source	Licence
OSV.dev	CC-BY 4.0 — GitHub Advisory Database