Thus the for a live instance depends on the server time when the APK was run.
Python script:
(X ^ T) & 0xFFFF = 0xCA7 => X ^ T = 0xCA7 (mod 65536) => X = T ^ 0xCA7 (mod 65536) So X is between 0 and 65535, but we need a 6-digit decimal representation with digit sum 24. apk time graveyard pin
Button enter = findViewById(R.id.btn_enter); EditText pinInput = findViewById(R.id.pin_input); enter.setOnClickListener(v -> { String pin = pinInput.getText().toString(); if (checkPin(pin)) { Toast.makeText(this, "Graveyard opened! Flag: CTF{" + pin + "}", Toast.LENGTH_LONG).show(); } else { Toast.makeText(this, "Rest in peace... wrong PIN.", Toast.LENGTH_SHORT).show(); } }); Found in the same class: Thus the for a live instance depends on