The Avengers actress was targeted by hackers in 2011, with several nude photographs leaked online as a result of the incident.
While the man responsible for the hacking was later arrested, Johansson has revealed that she struggled to come to terms with the crime and felt sceptical of those closest to her.
"It was really terrible; I felt absolutely violated. I wasn't really aware of how vulnerable all of us are, but I think everybody is just discovering that now, especially with the recent phone-hacking scandals. It isn't just celebrities, it's all kinds of people who are not asking for the spotlight," she explained in a new interview with Stylist.
"Being hacked made me feel more vulnerable than I ever had previously. I couldn't figure it out. For a while, I thought it must be someone that I knew who was posting these pictures of me and that was making me incredibly paranoid. I was looking around at all of my friends, who I have known for 20 years, wondering who the backstabber was."
Johansson went on to say that she was grateful to discover that no-one close to her had betrayed her, adding: "To find out it wasn't a friend who hacked in was a relief, oddly."
> Scarlett Johansson addresses nude photo leak: 'I'm entitled to privacy'
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