CVE-2026-49452

MediumCVSS 6.5

Published: 18/08/2026(UTC)Updated: 19/08/2026(UTC)Translated: 19/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.27%

20th percentile - higher than 20% of all known CVEs

Summary

WeasyPrint before 69.0 embeds unescaped HTML presentational-hint attribute values into CSS in weasyprint/css/__init__.py when presentational_hints=True. The background attribute is inserted into a background-image:url() declaration and parsed by tinycss2.parse_blocks_contents(), allowing untrusted HTML to inject additional CSS declarations. Applications that render untrusted HTML with presentational hints enabled can be affected by CSS injection and server-side requests through injected url() values.

Risk Assessment

An attacker can inject CSS or trigger server-side requests, potentially leading to data leakage or using the server as a proxy.

Recommendation

Update WeasyPrint to version 69.0 or later.

Original NVD description (English source)

WeasyPrint helps web developers to create PDF documents. Prior to 69.0, WeasyPrint embeds unescaped HTML presentational-hint attribute values into CSS in weasyprint/css/__init__.py when presentational_hints=True. The background attribute is inserted into a background-image:url() declaration and parsed by tinycss2.parse_blocks_contents(), allowing untrusted HTML to inject additional CSS declarations. Applications that render untrusted HTML with presentational hints enabled can be affected by CSS injection and server-side requests through injected url() values. This issue is fixed in version 69.0.