WeasyPrint helps web developers to create PDF documents. Prior to 70.0, the image-loading path in weasyprint/images.py passes fetched image bytes from HTML img URLs, CSS image values, SVG image references, and data URIs to Pillow's generic image dispatcher without excluding EPS or PostScript formats. On hosts with Ghostscript installed, Pillow EpsImagePlugin invokes the interpreter for attacker-controlled PostScript, which can produce interpreter-permitted effects and can lead to remote code execution when the installed Ghostscript version has a usable sandbox bypass.
Hosts without Ghostscript do not reach this rasterization path. This issue is fixed in version 70.0.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
Weakness Type (CWE)
References 3
https://github.com/Kozea/WeasyPrint/commit/39cd37ce1610bd890388e26591c569db1cba…
security-advisories@github.com
https://github.com/Kozea/WeasyPrint/releases/tag/v70.0
security-advisories@github.com
https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-r543-q48m-4c9j
security-advisories@github.com