This is the challenge:

This is the submitFlag function:

It decodes the string k3FElEG9lnoWbOateGhj5pX6QsXRNJKh///8Jxi8KXW7iDpk2xRxhQ== which is base64 encoded, and also DES encrypted.

Let’s hook this function using this frida script:

Java.perform(function (){
	var k = Java.use("b3nac.injuredandroid.k");
	k["a"].implementation = function (str) {
	    console.log(`k.a is called: str=${str}`);
	    let result = this["a"](str);
	    console.log(`k.a result=${result}`);
	    return result;
	};

})

Okay, the flag is {This_Isn't_Where_I_Parked_My_Car}.

We could have hook also the compare function, using same method as on Login.