Cybercriminals have been selling remote desktop protocol (RDP) access to compromised machines on business networks through Dark Web marketplaces, according to July 2018 research from McAfee. Bad actors can do a lot with this access, including committing other acts of fraud and facilitating data breaches.

Given the widespread use of the protocol, organizations should implement basic security measures and password hygiene practices to protect themselves from this threat.

Dark Web Shops Offer Cheap Access to Breached Systems

While analyzing underground web marketplaces, the McAfee Advanced Threat Research team came across several “RDP shops” selling access to vulnerable systems. Some of these shops offered access to more than a dozen connections. Others, most notably the Ultimate Anonymity Service (UAS), had more than 40,000 links up for sale.

Most of these systems consisted of computers running Windows XP through Windows 10, with Windows 2008 and 2012 Server the most prevalent at 11,000 and 6,500 links, respectively. Access to those systems ranged in value from $3 to $19, with dozens of connections linked to healthcare institutions. McAfee’s most significant find was an offering that promised access to the security and building automation systems of a major international airport for just $10.

RDP Access: A Versatile Threat

Flashpoint cybercrime analyst Olivia Rowley explained that RDP access is such a hot commodity because attackers can use it to facilitate a wide variety of crimes.

“For some cybercriminals, it may be more advantageous to use a compromised RDP as a staging ground for conducting other fraud, such as making a fraudulent purchase,” Rowley said, as quoted by Dark Reading in November 2017. “Cybercriminals may also find that the compromised RDP contains sensitive files or other proprietary information, thus making the RDP a tool for conducting data breaches.”

A proprietary protocol from Microsoft, the RDP potentially leaves enterprises exposed to attackers because it allows users to control computers over a network remotely. While it’s designed to help simplify administrative tasks for businesses, attackers can abuse the protocol to remotely access computers on an internal network, including those containing sensitive information. They can then either steal that information or conduct a Samsam ransomware attack to extort payments from victims.

How Can Companies Thwart RDP Attacks?

To minimize the threat of RDP attacks, according to the McAfee report, organizations should disallow RDP connections over the open web, restrict the number of failed login attempts before an account is locked and use multifactor authentication (MFA) to make brute-force attacks more difficult.

Perhaps most importantly, security leaders should work to increase cyber awareness among employees — especially as it relates to password hygiene — through continuous training and education.