CVE-2026-28348 (GCVE-0-2026-28348)

Vulnerability from cvelistv5 – Published: 2026-03-05 19:49 – Updated: 2026-03-06 17:55
VLAI
Title
lxml_html_clean: CSS @import Filter Bypass via Unicode Escapes
Summary
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.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-06 17:55 UTC
CWE
  • CWE-116 - Improper Encoding or Escaping of Output
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7775 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
fedora-python lxml_html_clean Affected: < 0.4.4
guessed Create a notification for this product.
Show details on NVD website
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