lxml is vulnerable to cross-site scripting (XSS). An attacker is able to inject and execute arbitrary script via HTML action attribute into defs.link_attrs (in html/defs.py).
bugs.launchpad.net/lxml/+bug/1888153
github.com/lxml/lxml/commit/10ec1b4e9f93713513a3264ed6158af22492f270
github.com/lxml/lxml/commit/a5f9cb52079dc57477c460dbe6ba0f775e14a999
github.com/lxml/lxml/pull/316
github.com/lxml/lxml/pull/316/commits/10ec1b4e9f93713513a3264ed6158af22492f270
lists.debian.org/debian-lts-announce/2021/03/msg00031.html
lists.fedoraproject.org/archives/list/[email protected]/message/3C2R44VDUY7FJVMAVRZ2WY7XYL4SVN45/
lists.fedoraproject.org/archives/list/[email protected]/message/XXN3QPWCTQVOGW4BMWV3AUUZZ4NRZNSQ/
security.netapp.com/advisory/ntap-20210521-0004/
www.debian.org/security/2021/dsa-4880
www.oracle.com/security-alerts/cpuoct2021.html