A cybercriminal group called Outlaw is using a Perl Shellbot to go after large organizations’ Internet of Things (IoT) devices.
The Trend Micro Cyber Safety Solutions Team observed a Perl Shellbot exploiting CVE-2017-1000117 to distribute an Internet Relay Chat (IRC) bot. This vulnerability enables attackers to pass a crafted “ssh://…” URL to unsuspecting victims and execute programs on their devices. According to Trend Micro, this threat can affect enterprise IoT devices, Linux servers, Windows-based environments and Android devices.
Outlaw communicates with the botnet using two compromised servers that belong to a Japanese art institution and a Bangladeshi government website. The threat group linked these two servers to a high-availability cluster to host an IRC bouncer and leveraged this asset for command-and-control (C&C) to target large businesses in more than a dozen countries, including the U.S., Germany, Israel and Japan.
The Ongoing Threat of IRC Botnets
IRC botnets are nothing new. In late 2016, MalwareMustDie observed attackers using new malware they called Linux/IRCTelnet to perform distributed denial-of-service (DDoS) attacks via an IRC botnet. More than a year later, Arbor Networks reported that attackers had used MedusaIRC and its IRC-based C&C to craft MedusaHTTP, an HTTP-based DDoS botnet written in .NET.
Unfortunately, it’s not difficult for cybercriminal groups like Outlaw to create this type of threat. Trend Micro observed that the code Outlaw used in its attacks is available online. Anyone can use that code to create a bot with an undetectable toolset.
How to Protect Enterprise IoT Devices From Outlaw
To protect their organizations against Outlaw’s activity, Trend Micro recommended monitoring for the creation of new accounts and restricting the use of FTP as much as possible. Security teams should also use reliable threat intelligence to block known malicious URLs and invest in security information and event management (SIEM) technology to identify unknown threats.