Xctf mobile--rememberother problem solving

1. take apk Drag in jdx in

2. analysis checkSN() function ,

3. Resource file found md5

 4. website Decrypt （MD5 Isn't it irreversible ？）

 

5. Submit the answer and find an error , Compressed package open apk, There are two files in it .

  open .docx

open writeup not have understood until then .

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