How threat actors hide PHP and ASP command execution stubs inside valid image files and how security teams scan for them.
Attackers inject <?php system($_GET["cmd"]); ?> into EXIF comment tags of valid JPEG images. If an application server has local file inclusion (LFI) or evaluates uploads, the shell triggers.
Automated regex scanners detect unescaped PHP open tags and execution primitives across both metadata segments and trailing byte partitions.
Security Analyst and Aspiring Security Engineer passionate about digital image forensics, OSINT research, CTF steganography challenges, and client-side application security.
Learn how penetration testers evaluate image upload filters and how application security teams enforce strict re-encoding and sandboxing.
Why SVG is an XML document capable of executing JavaScript, and how to safely sanitize vector uploads using DOMPurify and strict CSP.