VULNERABILITY INTELLIGENCE
CVE-2026-28348
CVSS score6.1 MEDIUM
EPSS probability0.28%
CISA KEVNot currently listed
Published2026-03-05
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Description
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.
Weakness classification
- CWE-116: Improper Encoding or Escaping of Output
Primary references
- security-advisories@github.com — Patch
- security-advisories@github.com — Exploit, Vendor Advisory
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 — Exploit, Vendor Advisory