Posted by Helen Martin on May 26, 2016
The recently encountered Petya trojan comes as something of a blast from the past: it infects the Master Boot Record (MBR) and encrypts the Master File Table (MFT). Kaspersky Lab's Fedor Sinitsyn has a good description of the trojan in a blog post, in which he points out that, far from being anything new, infection of the Master Boot Record (MBR) and encryption of files was seen as far back as 1994, when the One_Half virus infected MBRs and encrypted the disk contents.
Back in October 1994, it was the founder of Kaspersky Lab, Eugene Kaspersky himself, who provided a detailed analysis of One_Half for VB.
The multi-partite virus used some of the techniques developed by the Dark Avenger in Commander_Bomber, a virus that had caused numerous problems for researchers by inserting its code into a random location within an infected file. The fact that One_Half could also encrypt vital parts of the fixed disk complicated matters still further. Kaspersky concluded that One_Half posed many problems to the developers of anti-virus software, was worthy of further attention, and that great care should be taken when removing it from an infected disk.