Bulgarian companies have lost at least EUR 3 M over hack attacks in the past seven months, alone, an official said on Sunday.

The sum is equivalent to damages incurred only through the so-called "man-in-the-middle" approach, Yavor Kolev, who heads the country's Transborder Organized Crime department with the Chief Directorate for Combating Organized Crime (GBDOP), told public broadcaster BNT.

He pointed out that there had been instances of Internet banking scams as well. To this end, hackers use the computer of an accountant who left for lunch, with their electronic signature turned on.

The term "man-in-the-middle attack" refers to a case where an attacker interferes in two-party communications, possibly taking control over it whilst making the parties believe they are only talking to each other. In the cases Kolev had in mind, he explained malware is normally sent as an attached file allowing that intercorporate communication is followed.

One of the factors allowing this to happen is the use of pirated software, Kolev warned.

Over the past two weeks alone, two of Bulgaria's "top 100" companies have been hit by hackers with damages worth EUR 150 000 and EUR 450 000 incurred by each of them, respectively.