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Archives → ARJ password recovery
Overview of ARJ password protection:
ARJ archiver uses a very weak encryption algorithm. This results in the fact that in case you have only one unencrypted file from the archive, then the password for this archive can be found instantly. ARJ encryption system has some other weaknesses. For example, one can find first 3 characters without using the exhaustive search, and the password testing is very fast.
File extensions: arj ARJ crypto algorithms: XOR with password ARJ encryption weakness: human factor, (very) weak algorithm Possible attacks against ARJ: brute-force / known-plaintext Attacks complexity: depends only on password length / 20
How can I recover ARJ password? If you've got unencrypted files from archive then use known-plaintext attack