This article was written in collaboration with the Freedom of the Press Foundation and cross-posted on the Dangerzone blog. One of the oft-repeated sound bites of computer security advice is: “Don’t open random attachments from strangers.” If you are a journalist, however, opening attachments and documents is part of your job description. Since journalists already have a lot of security threats to worry about in dealing with sources, the safe opening of documents should not be one of them.