CVE-2026-55073
WeasyPrint helps web developers to create PDF documents. Prior to 70.0, server-side applications that configure a restrictive url_fetcher and pass attacker-influenced values to HTML.write_pdf() can have the restriction bypassed through the xmp_metadata or stylesheets options. In weasyprint/pdf/init.py, xmp_metadata calls select_source() without the document url_fetcher, allowing an accessible local file to be read and embedded verbatim in the output PDF. In weasyprint/document.py, stylesheets constructs CSS() without the document url_fetcher, allowing local or internal resource loading and propagating the permissive fetcher through nested CSS imports and url() references. The stylesheets channel applies fetched resources but does not by itself disclose stylesheet comments verbatim. This issue is fixed in version 70.0.
What this means for your business
- An attacker can use it only with access to the machine itself, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 8% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 6.2 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N- Weakness
- CWE-918
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-14
- Last modified
- 2026-09-23
- Sources
- NVD