New versions of the SamSam ransomware will not execute unless the person running the malware's payload enters a special password via the command-line.
This is a new protection mechanism added by the SamSam crew in a recent SamSam version discovered by Malwarebytes researchers.
Previous versions did not feature this mechanism, meaning anyone who found a SamSam binary could have infected his computer by double-clicking and running the file.
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