We’re receiving reports that Facebook is being used as a new vector for executing malware attacks, specifically as a means to distribute the Locky ransomware. While the ransomware variant is not being hosted directly on Facebook, this new version is being hosted in a peculiar way.
Once on that site, a popup is pushed to the user asking them to download a certain extension on your machine in order to view the video. After the extension has been installed, the attackers have the ability to view and alter data regarding the websites you visit, as well as access your Facebook account in order to message all of your friends with the same SVG file.
The payload is delivered through the Nemucod downloader Trojan, which has been known to download copies of Locky on victim’s PCs.
While Google and Facebook have been made aware of this attack, it is possible that proper remediation could take time. The best course of action if you receive such a message is to ignore it, clear your conversation history with that person, and report them to Facebook as having a compromised account.
If you have already been infected by this attack, there’s not much you can do outside of removing the offending extension in Chrome by going to Menu > More Tools > Extensions and check to see if either Ubo or One extensions are listed. This is also a good time to remove any unknown extensions that are installed as well.
Remember, once you have been locked out of your system by a piece of ransomware, your options for recovery are only as good as the backups you have made. Keep your backups up-to-date, and save your data on an outside drive as frequently as possible. Once a ransomware infection has taken place, any attached drives to your network are at risk. Never keep your backup drives attached to your machine when they are not in use.