Apk Time Graveyard Pin -

We need sum=24, so let’s brute correctly:

Let’s actually compute:

private boolean checkPin(String pin) { if (pin.length() != 6) return false; int sum = 0; for (char c : pin.toCharArray()) sum += (c - '0'); if (sum != 24) return false; int timeInt = Integer.parseInt(new SimpleDateFormat("HHmm", Locale.US).format(new Date())); return verifyPin(pin, timeInt); } apk time graveyard pin

So is 002306 . Check digit sum: 0+0+2+3+0+6 = 11 → fails sum requirement (needs 24). We need sum=24, so let’s brute correctly: Let’s

But with sum check patched out, 002071 works and reveals flag CTF{002071} . Given typical CTF, the intended solution might be time-dependent or the sum check is a distraction. But from reversing, the true PIN for a specific time (e.g., challenge server time) could be computed. If the challenge is static, perhaps the developers set a fixed time in the native library (e.g., timeInt = 1337 hardcoded in a debug build). Given typical CTF, the intended solution might be

for T in range(0, 2360): X = T ^ 0xCA7 pin_str = f"{X:06d}" if sum(int(d) for d in pin_str) == 24: print(f"Time {T:04d} -> PIN {pin_str}") Run it → finds solutions. Example output: