Spin And Win - Mobile Hacking Community CTF Writeup

Challenge Info

Field	Details
CTF	Mobile Hacking Community CTF
Challenge	Spin And Win
Category	Android / Reverse Engineering

Description

A vulnerable app stores sensitive data using insecure methods. Can you uncover where they’re hidden and retrieve them all?

Solution

Using ADB we can search it one by one

1. Shared Preferences

In the dir /data/data/com.just.mobile.sec.challenge_1/shared_prefs, we can run cat com.just.mobile.sec.challenge1.FlagHintActivity.xml

1. Databases

In the dir /data/data/com.just.mobile.sec.challenge_1/databases

vbox86p:/data/data/com.just.mobile.sec.challenge_1/databases # sqlite3 app-database
SQLite version 3.28.0 2020-05-06 18:46:38
Enter ".help" for usage hints.
sqlite> .tables
Flags              android_metadata   room_master_table
sqlite> select * from Flags;
1|Flag_Part_2: svji4wiecm
sqlite>

1. External Storage

In the dir /storage/emulated/0/Android/data/com.just.mobile.sec.challenge_1/files/InsecureStorage,

vbox86p:/storage/emulated/0/Android/data/com.just.mobile.sec.challenge_1/files/InsecureStorage # ls
VulnerableFile
cat VulnerableFile
Flag_Part_3: eho7r4np}

Flag

FLAG:MHC={4n0hzeesvji4wiecmeho7r4np}