New ShellBot DDoS Malware Variants Targeting Poorly Managed Linux Servers
Mar 21, 2023
Linux / Server Security
Poorly managed Linux SSH servers are being targeted as part of a new campaign that deploys different variants of a malware called ShellBot. "ShellBot, also known as PerlBot , is a DDoS Bot malware developed in Perl and characteristically uses IRC protocol to communicate with the C&C server," AhnLab Security Emergency response Center (ASEC) said in a report. ShellBot is installed on servers that have weak credentials, but only after threat actors make use of scanner malware to identify systems that have SSH port 22 open. A list of known SSH credentials is used to initiate a dictionary attack to breach the server and deploy the payload, after which it leverages the Internet Relay Chat ( IRC ) protocol to communicate with a remote server. This encompasses the ability to receive commands that allows ShellBot to carry out DDoS attacks and exfiltrate harvested information. ASEC said it identified three different ShellBot versions – LiGhT's Modded perlbot v2, DDoS ...