Hidden Webshell: Identical MD5 Hash PHP Files

2025-09-24
Hidden Webshell: Identical MD5 Hash PHP Files

Two PHP files share the same MD5 hash, but one is a webshell. This technique allows attackers to bypass cached webshell detection. A hexdump reveals subtle differences between the files, resulting in identical MD5 hashes despite vastly different functionality. This highlights the insufficiency of relying solely on MD5 hashing for security checks; a more comprehensive security strategy is needed.