write-ups-challenges-2022-2023/rise-of-the-androids/SOLUTION.md

Difficulty

Medium, 35 points

How To Solve

1. Decompile the APK, (e.g. using JADX or online: http://www.javadecompilers.com/apk).
2. Figure out the (rather simple) logic of the app, which is located in the MainActivity.java file:
   • The decoded flag is shown in a toast whenever the code is correct.
3. The code is a construction of strings fetched from resources/res/values/strings.xml.
4. Reconstruct the code, enter the code in the app and the flag will be shown.

The correct code is 7402583711.

Flag

IGCTF{Sp0tt3dTheAndr01dUser}