The groups behind Mirai and variants of the Internet of Things (IoT) device infector are increasingly targeting businesses, with nearly one-third of attacks in recent months focusing on devices commonly used inside companies, IBM's X-Force security research group says.
Companies have encountered about twice as many attacks by variants of Mirai in 2019 versus 2018, with more than 63 device-infecting programs seen to date this year, according to IBM X-Force. Specifically, three new Mirai variants — Gafgyt, Shaolin, and Loli — target enterprise devices to drop denial-of-service or cryptomining software on the compromised systems.
"If your organization is using IoT devices, or if you're unsure of its use of IoT devices, you should be concerned," says Charles DeBeck, senior cyberthreat intelligence analyst at IBM. "Threat actors are actively targeting this space and developing malware for it, which indicates not only a capability to target IoT, but also that targeting it would be profitable. This means IoT malware isn't going away anytime soon."
The move to attack business infrastructure is a natural evolution for the bad guys. While enterprise systems tend to be better protected, they also are connected to the Internet via higher bandwidth connections, making them more valuable to cybercriminals once compromised.
In March, Palo Alto Networks described a new version of Mirai malware that included 11 new exploits, of a total of 27, targeting WePresent presentation systems and LG Supersign TVs that are sold to businesses.
"[T]argeting enterprise vulnerabilities allows [attackers] access to links with potentially larger bandwidth than consumer device links, affording them greater firepower for DDoS attacks," wrote Palo Alto's Ruchna Nigam, a senior security researcher, in an alert on the attack.
Mirai is malware, first discovered in 2016, that infects devices not traditionally targeted by malware, such as home routers, digital video recorders, and other IoT products. The compromised devices have historically been used in massive distributed denial-of-service (DDoS) attacks that threaten businesses. Initial attacks against domain-name company Dyn and security journalist and researcher Brian Krebs used about 150,000 devices and generated more than 500 Gbps of traffic, according to Level3 Communications.
"These new attacks are alarming for their scope, impact, and the ease with which attackers employed them," stated Dale Drew, then chief security officer of Internet provider Level 3 Communications, in prepared testimony during a hearing before two subcommittees of the US House of Representatives just two months after Mirai first appeared. "Also worrisome is that these attackers relied on just a fraction of the total available compromised IoT nodes in order to attack their victims, demonstrating the potential for significantly greater havoc from these new threats."
Consumer devices will likely continue to be targeted because they are common and relatively insecure. In 2018, IBM saw a monthly average of 3,000 attempts to attack its customers with Mirai or Mirai-like malware. In 2019, that rate has roughly doubled.
In addition, IBM found attackers appear to be focusing on both the insurance and information services industries, accounting for more than 80% of attacks. While these industries could be seeing more attacks because they have a larger IoT footprint compared with other industries, that seems an unlikely explanation, IBM's DeBeck says.
"In our experience, increased levels of incidents generally indicate increased targeting, whether this targeting is intentional or unintentional," he says. "It is unlikely the trend of increased incidents is due to greater use of IoT technology in these sectors, as these fields have no particular affinity for IoT usage."
IoT devices tend to proliferate quickly inside companies' environments and are a common shadow IT problem, DeBeck says. Companies need to get a handle on just how widespread the devices are, he says.
"The first step any organization needs to take is to inventory what IoT devices are in their network. Without full visibility, you can't protect anything," he says.
Every device should have someone responsible for managing it, including patching it regularly, monitoring it for unusual activity, and securing the device's iteraction with other enterprise IT.