CVE-2026-28348GHSA-HW26-MMPG-FQFGPYSEC-2026-2201
lxml_html_clean: CSS @import Filter Bypass via Unicode Escapes
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 0.4.4
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: poc
- Automatable: no
- Technical impact: partial
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.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: poc · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- fedora-python lxml_html_clean
fixed in 0.4.4
- lxml-html-cleanPyPI
fixed in 0.4.4