According to Neon Revolt, the image of Silverman is real:
[T]he only editing used on the photo was . . . to mask some wrinkles . . . . The image on the phone was, evidently, not photoshopped, nor was this simply a case of someone slapping a hand holding a phone over Sarah Silverman’s dimly-lit face. No, this was Sarah legitimately thinking she could intimidate the “Internet Hate Machine” by taking a selfie with some text on it.