Stirling-PDF: SVG→PDF local file read (LFI) via SVG-sanitizer and Batik same-origin bypass

What we know

Description

Stirling-PDF is a locally hosted web application that facilitates various operations on PDF files. From 2.13.1 until 2.13.2, the POST /api/v1/convert/svg/pdf endpoint renders attacker-supplied SVG through Apache Batik, and a scheme-less root-relative image reference bypasses SvgSanitizer.isExternalUrl() before Batik resolves it against the file:///input.svg document base as a same-origin local file. The convert() and addSvgAsPage() paths in app/core/src/main/java/stirling/software/SPDF/utils/SvgToPdf.java can then render image-decodable server files into the returned PDF when sanitization is enabled, including without authentication on login-disabled deployments or with non-admin access when login is enabled. The issue discloses PNG, JPG, GIF, or SVG content and provides an existence oracle only for image-decodable paths; plain text, binary files, directories, XInclude text, external entities, explicit file URLs, and tested HTTP references are not disclosed through this mechanism. This issue is fixed in version 2.13.2.

From GitHub_M

Affected and fixed versions

Exploit code

References