Bad Bots Increasingly Hide Out in Cloud Data Centers

Bots became a household term last year in the wake of Russian election-meddling in the US and their inordinate presence on social media platforms. The population of these malicious bots also grew by nearly 10% last year, accounting for one-fifth of all website traffic.

So-called bad bots also execute online fraud, data theft, and distributed denial-of-service attacks, and despite more awareness as well as moves by Twitter and others to purge them, they continue to dog e-commerce and evolve their tactics to evade detection, according to a new analysis of bot activity by Distil Networks that studied hundreds of billions of bad bot requests on thousands of websites.

Humans accounted for nearly 58% of website traffic in 2017, with the rest bad bots (21.46%) and good bots (20.74%). Good bots include tools like search engine crawlers, while bad bots are everything from trolls to illicit data-scraping tools and proxies for cybercrime. Most bad bots live on gambling (53.1%) and airline (43.9%) websites, and most (83.2%) pose as Web browser-users, including Chrome, Firefox, Internet Explorer, and Safari, and 10.4% as mobile browsers (Safari, Android, and Opera).

The biggest shift in 2017 was bots hiding out in data centers: some 82.7% are now operating out of cloud-based accounts versus 60.1% in 2016, the data shows.

Anna Westelius, senior director of security research at Distil, says bad bots are waging credential-stuffing attacks en masse. While account takeover attacks on average occur two to three times per month, after a data breach occurs, account takeover attacks increase threefold, according to Distil's data.

"They are trying them wherever they can," Westelius says of the stolen credentials.

They're also mimicking human behavior more convincingly, by executing JavaScript like a browser, or faking mouse movements. "A lot of the time, bad bots are utilizing human connections, like human smartphone connections," Westelius says. "A lot of these are malware-related botnets" that want to appear as human as possible in their communications and behaviors, she says.

Distil found that 5.8% of all mobile devices on cellular networks are used in bad bot attacks. These bots are considered the most advanced or sophisticated because they are less likely to get detected. Overall, 74% of bad bot traffic today is sophisticated or moderately sophisticated, the report says.

But operating out of cloud data centers is all the rage for bot runners now. It's inexpensive to spin up a cloud server, for example, and it appears legit. "Hosting provides really offer them a legal way to highly distribute themselves. It's cheap and accessible," Westelius says.

The move to the cloud coincided with a decrease in residential bot traffic, according to Distil. "The economics and success of using low-cost cloud data centers probably explains why there was a drop in the amount of traffic from residential ISPs, falling from 30.5% to 14.8% in 2017," the report said.

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