According to a report from IBM's X-Force team, the anonymous TOR network is increasingly being used to support ransomware schemes and other Internet attack scenarios. Big Blue warned companies and ISPs to start blocking TOR traffic from their networks.

Ransomware, which encrypts the victim's hard drive and demands payment to release the data, is a growing phenomenon around the world. According to the report, attackers use the TOR network to communicate with the victim and transfer monetary payments.

The reports states that the success of the TOR network as a vehicle for petty end-user ransomware attacks and SQL injection has emboldened the perpetrators, and TOR is now used for botnet control and sophisticated industrial espionage.

Although TOR services are intended to be hidden and anonymous, organizations can still take steps to keep them off the network. The report includes recommendations such as:

• Prohibiting the use of unapproved encrypted proxy services
• Prohibiting the use of personally subscribed proxy services
• Prohibiting the download and installation of unapproved software
• Prohibiting the use of personally owned removable devices
• Prohibiting computers from booting to media other than the hard drive
• Using publicly available lists of proxy nodes to block network traffic to and from listed sites
• Implementing a comprehensive desk audit program

The TOR network also has legitimate functions, such as supporting the free speech rights of users in totalitarian countries. Many innocent users implement a TOR node for ideological or political reasons without realizing the node could also be used to stage criminal activities.