HTML Cleaner allows crafted and SVG embedded scripts to pass through

Moderate

scoder published GHSA-55x5-fj6c-h6m8

Dec 12, 2021

Package

lxml (Python)

Affected versions

<4.6.5

Patched versions

4.6.5

Description

Impact

The HTML Cleaner in lxml.html lets certain crafted script content pass through, as well as script content in SVG files embedded using data URIs.

Users that employ the HTML cleaner in a security relevant context should upgrade to lxml 4.6.5.

Patches

The issue has been resolved in lxml 4.6.5.

Workarounds

None.

References

The issues are tracked under the report IDs GHSL-2021-1037 and GHSL-2021-1038.