- Published on
Android CTF Juicy Bar::Code Obfuscation
- Authors
- Name
- Ajin Deepak
Welcome all,
I wanted to do a quick writeup series on the android ctf application called juicy bar. If you haven't tried it out yet please check it out. It's really nice and beginner friendly.
I will try to cover most of the challenges, but this will be very random. I won't be following any particular order. Okay, let's get on with the challenge already.
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We need two flags to complete this challenge. If you look at the hints, it says to use Jadx and look for an exception that may be thrown for a lateinit variable. Let's load the APK in the JADX.
Flag One
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This is the responsible class for this challenge. So let's examine the code based on the hints we got. Let's search for "throw".
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Okay we got something. Let's try pasting that string "scrtPreObfuscationVar".
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If you check the Logcat now, you should have received the flag. Okay now let's check the hints for the second flag.
Flag Two
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Let's check for the toString() method.
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Hmmm. This string "scrtLeakedByToString" looks interesting let's try that.
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Yes!! We got the second flag. The challenge is now completed.