Crater Invoice through 6.0.6 contains a path traversal vulnerability in the self-update API that allows authenticated company owners to write arbitrary files outside the intended extraction directory by supplying crafted ZIP archives with ../ sequences to the unzip endpoint. Attackers can exploit unsanitized ZIP entry names passed to PHP's ZipArchive::extractTo() to write arbitrary PHP files into the web-accessible public directory and achieve remote code execution on the server.