Researchers discover POS backdoor targeting the hospitality industry

ESET researchers have discovered ModPipe, a modular backdoor that gives its operators access to sensitive information stored in devices running ORACLE MICROS Restaurant Enterprise Series (RES) 3700 POS (point-of-sale) – a management software suite used by hundreds of thousands of bars, restaurants, hotels and other hospitality establishments worldwide.

The majority of the identified targets were from the United States.

Containing a custom algorithm

What makes the backdoor distinctive are its downloadable modules and their capabilities, as it contains a custom algorithm designed to gather RES 3700 POS database passwords by decrypting them from Windows registry values.

This shows that the backdoor’s authors have deep knowledge of the targeted software and opted for this sophisticated method instead of collecting the data via a simpler yet “louder” approach, such as keylogging.

Exfiltrated credentials allow ModPipe’s operators access to database contents, including various definitions and configuration, status tables and information about POS transactions.

“However, based on the documentation of RES 3700 POS, the attackers should not be able to access some of the most sensitive information – such as credit card numbers and expiration dates – which is protected by encryption. The only customer data stored in the clear and thus available to the attackers should be cardholder names,” cautions ESET researcher Martin Smolár, who discovered ModPipe.

“Probably the most intriguing parts of ModPipe are its downloadable modules. We’ve been aware of their existence since the end of 2019, when we first found and analyzed its basic components,” explains Smolár.

Downloadable modules

• GetMicInfo targets data related to the MICROS POS, including passwords tied to two database usernames predefined by the manufacturer. This module can intercept and decrypt these database passwords, using a specifically designed algorithm.
• ModScan 2.20 collects additional information about the installed MICROS POS environment on the machines by scanning selected IP addresses.
• ProcList with main purpose is to collect information about currently running processes on the machine.

“ModPipe’s architecture, modules and their capabilities also indicate that its writers have extensive knowledge of the targeted RES 3700 POS software. The proficiency of the operators could stem from multiple scenarios, including stealing and reverse engineering the proprietary software product, misusing its leaked parts or buying code from an underground market,” adds Smolár.

What can you do?

To keep the operators behind ModPipe at bay, potential victims in the hospitality sector as well as any other businesses using the RES 3700 POS are advised to:

• Use the latest version of the software.
• Use it on devices that run updated operating system and software.
• Use reliable multilayered security software that can detect ModPipe and similar threats.