AES replacement remains uncracked in reduced key length 38 bit code breaking challenge.

Nobody could claim the price: 4.428 ounces (137.7 g) pure gold.
(PresseBox) (Bradford, Munich, Schoeffengrund, ) The AES replacement encryption algorithm by PMC Ciphers proved to be sufficiently secure in a one-month public code-breaking challenge at a drastically reduced key length of 38 bit. Any cipher with a keyspace limited to 40 bit is exempted from U.S. export restrictions since the 1990’s.

The challenge has ended on April 01, 2013. The task was to crack the passphrase of an encrypted PDF file. The hyperlinks to the PDF file, as well as to the C++ source code of the cipher, are readily available for free at The price was 4.428 ounces of gold worth approximately US-$ 7000.

The keyphrase was: P-07/1

There existed approximately 282 billion equally possible key combinations, which correspond with 38 bit.

“The royalty-free and improved open-source Polymorphic Medley Cipher Version 2 has proved to protect data efficiently, even if the length of the key is extremely short. Our technology is unique on the market and it appears if we are the only company in the world to provide best possible security even for short keys. After passing this totally unbiased and open challenge, we’re very confident that the cipher will be implemented in a number of civil projects that require a hardened AES cipher", says C.B. Roellgen from PMC Ciphers.

More information and can be found at:


PMC Ciphers, Inc
Josephsburgstr. 85
D-81673 Munich
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