Hiding in Plain Sight
This blog was written by Jon Munshaw and Jaeson Schultz.
Cisco Talos is continually working to ensure that our threat intelligence not only accounts for the latest threats but also new versions of old threats, such as spam. This often means pursuing cybercriminals wherever they congregate. However, instead of wheeling-and-dealing using hidden servers on some mysterious dark web address, a surprisingly large number of cyber scofflaws prefer to operate right out in the open using social media. For example, Facebook is host to dozens of groups that serve as online marketplaces and exchanges for cybercriminals. Talos saw spam from services advertised in these Facebook groups show up in our own telemetry data, indicating a potential impact to Cisco customers from these groups.
Over the past several months, Cisco Talos has tracked several groups on Facebook where shady (at best) and illegal (at worst) activities frequently take place. The majority of these groups use fairly obvious group names, including “Spam Professional,” “Spammer & Hacker Professional,” “Buy Cvv On THIS SHOP PAYMENT BY BTC 💰💵,” and “Facebook hack (Phishing).” Despite the fairly obvious names, some of these groups have managed to remain on Facebook for up to eight years, and in the process acquire tens of thousands of group members.
In all, Talos has compiled a list of 74 groups on Facebook whose members promised to carry out an array of questionable cyber dirty deeds, including the selling and trading of stolen bank/credit card information, the theft and sale of account credentials from a variety of sites, and email spamming tools and services. In total, these groups had approximately 385,000 members.
Talos initially attempted to take down these groups individually through Facebook’s abuse reporting functionality. While some groups were removed immediately, other groups only had specific posts removed. Eventually, through contact with Facebook’s security team, the majority of malicious groups was quickly taken down, however new groups continue to pop up, and some are still active as of the date of publishing. Talos continues to cooperate with Facebook to identify and take down as many of these groups as possible.