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PMC Ciphers Jan/Feb Code-breaking Challenge has ended: Nobody was able to break the 32 bit keyphrase!
January/February Code-breaking Challenge
: The first who would have broken a 32 bit keyphrase and who would have shown up in Munich, Germany on Feb. 12, 2012 would have got 1.329 ounces of gold worth approx. 2084 USD
UPDATE: January/February 2012 code-breaking challenge has ended on February 12, 2012, which is exactly four weeks after the geocache was buried. Nobody was able to break the 32 bit code!
The password was
Everybody who wishes to verify the password can download the encrypted video (see download links below)
, as well as the
and decrypt the data.
This is the original text:
Yes, even for keys as short as 32 bit we're very confident that our
GBPMC HASH/GBPMC_V1 hash/cipher combination is strong enough to withstand attacks carried out by enthusiasts and/or professionals for several weeks
Here's how you get the three golden coins each weighing 0.43 ounces of gold:
1.) Download an encrypted video file. The file with 3.8GB file size has been split into these eight pieces:
2.) Join the eight pieces using the free tool HJ-Split (
3.) Download the updated version of
the code breaker tool here:
4.) Run the
code breaker tool (64 bit Windows is required ! )
, select GBPMC HASH/GBPMC_V1 and limit keyspace to "only a-z and A-Z and 0-9". Finally hit the "Decrypt/Break File" button and then wait. In order to get the prize, you must show up in person on Feb. 12, 2012
at 11.11 CET in the restaurant (level A1) in the Olympic Tower in Munich, Germany.
The keyphrase is up to 6 characters long. The rightmost character is either "a", "b", "c" or "d". So the other characters on the left side might be any character "0" .. "9", "a..z" or "A..Z", but the trailing character is just one out of four possibilities". There exist exactly
(62^5 + 62^4 + 62^3 + 62^2 + 62^1 +62^0) * 4 = 3.724.605.612 possibilities for the keyphrase, which corresponds with 31.79 bit (2^31.7944405247).
If the movie was encrypted using AES, a keyphrase with 32 bit effective key length would be broken within minutes.
You don't believe it? Well,
here's an AES 128 bit- encrypted MP3 file for testing
. The file should be renamed to "aes128_ecrypted_mp3_file.mp3._ciphertext_" ! You'll find the password pretty soon with the
code breaker tool. S
elect "AES 128" and limit keyspace to "only a-z" or "
and A-Z and 0-9", if you want to spend much more time. The exhaustive search might take up to several minutes with the "only a-z" setting, depending on the CPU power of your processor. The more threads run in parallel, the faster will the correct key be found. Once you've found the key, simply enter it in the "password" line and click at the "Decrypt" button (the button caption is "Continue.." if the code breaker threads have just identified the key).
GBPMC_V1 cipher, things are totally different. The entire movie file needs to be loaded into RAM and the cipher actually needs to decrypt the entire block as each bit in the huge block depends on each other bit. This is why a 64 bit Operating System and at least 8Gb of RAM are required.
The code breaker tool that some folks will know from the last decryption challenge has been improved for more reliable dectection of the correct key and the GBPMC_V1 cipher has been optimized for 4 and 8 Gb block size.
Taking into account that gold is quite expensive these days - we are either very dumb to throw money out of the window or there is a good chance for us to keep the gold.
This challenge is clearly manageable for someone who can mount a distributed attack.
If only a bit more than half the people who live on this planet would choose a unique key that is within the keyspace of this challenge, one of them would definitely win the prize.
Who can take part and what is needed to take part at the challenge?
- everybody can !
- it's free !
you can even find the source code here !
The challenge has started on January 11, 2011