PostScript is a page-description language used to describe how text, graphics, and layout should be rendered on a page. Instead of being a simple image or document container, it can contain instructions that a printer or interpreter executes to produce output. Because of that, PostScript is often handled by server-side tooling such as document conversion engines and renderers.
In cyber security, PostScript matters because parsing it is not always passive: a crafted file may trigger complex interpreter behavior, resource exhaustion, or dangerous processing paths in tools like Ghostscript. Attackers can abuse upload features by submitting malicious PostScript files to applications that automatically generate previews, thumbnails, or converted documents. Defenders reduce risk by limiting who can upload files, isolating conversion services, keeping interpreters patched, and treating document processing as untrusted code execution rather than simple file handling.