I would agree with Andrew and also think ChasFisher's attempt sums it up better but still think that it can be even more condensed, You seem to have a very complex story that will be told throughout rather than set up in the opening, so you will have a lot to get into the short log line. I think you need to really focus on the main element that the protagonist is going to have to do.
'A brilliant hacker's life is put at risk by a new virus which destroys those who disobey the system, causing the hacker to fight against the people he has been leeching off in order to prevent certain death.'
Something like that although I know still a little all over the place. I think the idea is very interesting and definitely can go places.