Spammers are mass-messaging Facebook users with PDF files claiming to contain nude celebrity pictures, but which lead users to a malicious Chrome extension and overly aggressive advertising sites. The spam campaign was detected by Cyren researchers Magni Reynir Sigur..sson & Maharlito Aquino, who shared their findings with Bleeping Computer readers in advance. The extension has been removed, at the time of writing, the Cyren team said. In the extension’s source code, researchers also discovered the malicious code responsible for generating the spam.
Source: https://www.bleepingcomputer.com/news/security/facebook-spam-campaign-uses-chrome-extension-to-spread-nude-celebrity-pdfs/