phpMyFAQ - Authenticated Path Traversal in PDF Export via concatenatePaths Function

phpMyFAQ before 4.1.5 contains a potential authenticated path traversal vulnerability in the concatenatePaths() function within src/phpMyFAQ/Export/Pdf/Wrapper.php. A user with FAQ editing privileges can store HTML containing crafted image paths that are processed during PDF generation. The path resolution logic locates the substring "content" within a user-controlled path using strpos(); when "content" is absent, strpos() returns false, which becomes 0 when cast to an integer, preserving the entire attacker-controlled path. This path is later passed to file_get_contents() without canonicalization or root-directory containment validation, which may allow reading of files outside the intended content directory.