Brazilian police seized five hard drives when they raided the Rio apartment of banker Daniel Dantas as part of Operation Satyagraha in July 2008. But subsequent efforts to decrypt files held on the hardware using a variety of dictionary-based attacks failed even after the South Americans called in the assistance of the FBI.
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The case is an illustration of how care in choosing secure (hard-to-guess) passwords and applying encryption techniques to avoid leaving file fragments that could aid code breakers are more important in maintaining security than the algorithm a code maker chooses. In other cases, law enforcement officials have defeated suspects’ use of encryption because of weak cryptographic trade craft or poor passwords, rather than inherent flaws in encryption packages.