Security researchers recently spotted KBOT malware, the first “living” computer virus they’ve discovered in years.

Kaspersky Lab explained that it hadn’t seen a new computer virus in the past few years, but that changed when it observed KBOT injecting malicious code into Windows executable code as a means of spreading. The security firm explained that the malware functions as a “living virus” in that sense.

Upon further investigation, Kaspersky’s researchers noted that the malware penetrates a user’s computer via the web, the local network or an infected piece of external media. Once launched, the malware gains a foothold on the system by writing itself to Startup and the Task Scheduler. The virus then attempts to deploy web injects for the purpose of stealing a user’s personal and banking data. It also tried to load additional stealer modules designed to target a user’s logins, cryptocurrency wallet data and other information with the intent of sending this stolen data to its command-and-control (C&C) server.

A Look Back at Possible Earlier KBOT Activity

Kaspersky Lab’s researchers weren’t the first to discover a malware sample identified as KBOT. On the contrary, NoVirusThanks spotted a similar C&C bot all the way back in November 2012. In May 2016, Cofense detected several new phishing campaigns distributing Bolek, sophisticated malware derived from repurposed “Kbot” source code from Carberp. A few months after that, in October, BitSight observed that Bolek had begun targeting users in Ukraine and Poland.

The recent KBOT sample discovered by Kaspersky represents a more serious threat than these past possible iterations, however. According to the researchers, the threat “is able to spread quickly in the system and on the local network … significantly slows down the system through injects into system processes, enables its handlers to control the compromised system through remote desktop sessions, steals personal data, and performs web injects for the purpose of stealing users’ bank data.”

How Organizations Can Defend Against KBOT

Security professionals can help prevent a KBOT infection by using artificial intelligence (AI) and machine learning to increase their visibility into potentially suspicious behaviors on the network. Companies should also implement a multifaceted security strategy that controls access to enterprise resources and continuously monitors business-critical endpoints for malicious activities.