CVE-2026-28348
lxml_html_clean: CSS @import Filter Bypass via Unicode Escapes
CVSS Score
6.1
EPSS Score
0.0%
EPSS Percentile
0th
lxml_html_clean is a project for HTML cleaning functionalities copied from `lxml.html.clean`. Prior to version 0.4.4, the _has_sneaky_javascript() method strips backslashes before checking for dangerous CSS keywords. This causes CSS Unicode escape sequences to bypass the @import and expression() filters, allowing external CSS loading or XSS in older browsers. This issue has been patched in version 0.4.4.
| CWE | CWE-116 |
| Vendor | fedora-python |
| Product | lxml_html_clean |
| Published | Mar 5, 2026 |
| Last Updated | Mar 6, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
fedora-python / lxml_html_clean
< 0.4.4