Challenge 3.1

A reward of 2M satoshis is embedded in a lock box with a two hour time window:

Wed May 26 2021 22:00:00 GMT +/- 1 hour

The reward: https://www.blockchain.com/btc/address/bc1qa7dn06rv2h5kejwpkahw8ueqelpjlw8nta46g3

To claim the reward you will need to hack BTCTimeLockDecryption.exe before the timelock expires. This is a Windows x64 program.

In order to help you understand how to use BTCTimeLockDecryption.exe I’ve included a demo lock box.

Here is a zip file containing Challenge_3.1_DemoLockBox.bin

You’ll need to enter the BTC block header information for a block within the target time range in order to unlock the encrypted message inside the lockbox. The demo lock box works with the following block headers:

Here are valid settings for block 675647, one of the valid block for this lockbox.

Plug these values in, click Open TimeLock and you’ll see the encrypted message from the lockbox:

Use the following URL to access the block header values for this block: https://blockchain.info/rawblock/675647

Here’s the password for Challenge_3.1_DemoLockBox.bin: 50A812BC-431E-4C14-9561-1930C8D6C5B7

You may easily copy and paste values from the above URL (modified) for any block.

Here’s the lockbox file with the 2M satoshi reward:

The password for Challenge_3.1_data.bin is: A459D5B9-C619-432B-9176-2558E39028C8

I will be sweeping the private key with this BTC reward a few hours before this challenge expires if no one has successfully hacked the lock box by then.

Note: BTCTimeLockDecryption.exe does not access the internet at all.

Happy hacking!