Bug 2533208 (CVE-2026-55073)

Summary: CVE-2026-55073 weasyprint: WeasyPrint: Local file read and Server-Side Request Forgery (SSRF) via URL fetcher bypass
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: dschmidt, jlanda, kshier, simaishi, stcannon, teagle, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in WeasyPrint. 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. This allows an attacker to read local files or perform Server-Side Request Forgery (SSRF) by loading internal resources. The primary impact is information disclosure and the ability to access internal network resources.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2536876, 2536877    
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Description OSIDB Bzimport 2026-09-14 17:19:04 UTC 
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.