The Soviet VIC cipher used in the early 1950s, long known for being complex and secure, may not be as impossible to crack as initially assumed.
According to a recent article published in Cryptologia, “Soviet VIC Cipher: No Respector of Kerckoff’s Principles,” cracking the infamous Soviet VIC cipher is possible if one understands the enciphering algorithm. If one does not know the algorithm, according to the article’s author Jozef Kollar, the cipher indeed lives up to its reputation, and becomes nearly impossible to decipher.
The Soviet VIC Cipher, initially used by the Soviet spy Reino Hayhanen, was believed to be one of the most elaborate hand ciphers of its time. When the United States FBI became aware of the cipher, attempts to decipher it were met with little success. According to Kollar, the FBI was not able to crack the cipher until Hayhanen himself defected to the United States in 1957.
However, Kollar asserts that the cipher “consists of a checkerboard substitution followed by two transpositions,” and “cracking such a substitution alone is not much more difficult than cracking a simple monoalphabetic substitution.” Agent Hayhanen used five different parts in his cipher, the first four followed consistent patterns and the last was random.
To crack these parts, one must follow a specific key (which includes Hayhanen’s personal information, a specific password, and the date of the Soviet victory over Japan), and three specific permutations. Kollar outlines the precise steps to decryption in his article.
Ultimately, it appears that the Soviety VIC cipher, long known for its impenetrability and difficulty, may not be as impossible to crack as initially believed. As long as one knows the enciphering algorithm, this well-known cipher could indeed be solvable, and one of the biggest mysteries of its time could finally be cracked.