# Day 19

#### Task 25 — Game hacking Day 19: I merely noticed that you're improperly stored, my dear secret! <a href="#daec" id="daec"></a>

**1. What is the OTP flag?**

1. Start your machine.
2. Open the TryUnlockMe folder, right-click and open a terminal inside that folder.
3. Enter the following command, `frida-trace ./TryUnlockMe -i 'libaocgame.so!*'`
4. Now, Navigate to `/home/ubuntu/Desktop/TryUnlockMe/__handlers__/libaocgame.so/`
5. Open the `_Z7set_otp.js` file or a file with `set_otp` keyword.
6. Modify the code as below and interact with the game.

```perl
CopydefineHandler({
  onEnter(log, args, state) {
    log('_Z7set_otpi()');
    log("OTP:" + args[0].toInt32());
  },
  onLeave(log, retval, state) {
  }
});
```

7\. Now, see the terminal an OTP number will be displayed, paste that in the game to get the flag.

```css
CopyAns: THM{one_tough_password}
```

**2. What is the billionaire item flag?**

Open and modify the purchase file as below, interact with the game and try to purchase the flag.

```perl
CopydefineHandler({
  onEnter(log, args, state) {
    log('_Z17validate_purchaseiii()');
    args[1] = ptr(0)

  },

  onLeave(log, retval, state) {
      
  }
});
Ans: THM{credit_card_undeclined}
```

**3. What is the biometric flag?**

Modify the Biometric file with the below one and interact with level 3

```perl
CopydefineHandler({
  onEnter(log, args, state) {
    log('_Z16check_biometricsPKc()');
    log("PARAMETER:" + Memory.readCString(args[0]))
  },

  onLeave(log, retval, state) {
    retval.replace(ptr(1))
  }
});
Ans: THM{dont_smash_your_keyboard}
```


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