11-20.7z May 2026

The first step is always to identify what you are dealing with. Using the file command in Linux or a hex editor like 010 Editor helps verify the file header. : file 11-20.7z

: If the archive is password-protected, look at the filename. In some CTFs (like CodeBattle ), the password is the Base64-decoded version of the filename or a string found in the file metadata. 11-20.7z

Many "nested zip" challenges use a pattern where the filename itself is the key. The first step is always to identify what