When Rogue Insiders Go to the Dark Web

Researchers who operate undercover in the Dark Web are noticing an increase in activity among rogue employees selling access and stolen data from their organizations — mainly financial and telecommunications companies — for profit.

Charity Wright, cyber threat intelligence analyst and researcher at IntSights, says the rogue employee, often working via underground brokers, is a growing phenomenon in the Dark Web. Researchers have observed sellers, especially in Russian language-speaking forums, openly discussing how they offer services where they steal and sell information from their employers.

The researchers spotted a pair of telecommunications employees selling text message logs and geolocation information from phone SIM cards, for example. "There's huge potential for damage if they use it to target VIPs or government employees," for instance, Wright notes. "These services are relatively cheap, and all you have to do is provide them a phone number and they can give you everything they have on it."

Rogue financial firm employees typically get paid more: Brokers offer 10 times more money for information supplied by bank insiders. "Because they have the keys to the kingdom ... with customer bank information they have access to, and deals that are being closed, for insider trading," she says.

IntSights has been studying the rogue insider trend in the Dark Web for the past four years. In 2017, IntSights and RedOwl published a report, "Monetizing the Insider: The Growing Symbiosis of Insiders and the Dark Web," on their two-year study of Dark Web forums that recruit insiders. At the time, they noted a twofold increase in insider outreach and forum discussions between 2015 and 2016. 

Insider recruits go through an elaborate selection and verification process by the forums, including confirming the access the insider has within its organization and how fast they can grab it and release it. Once they are in, they are protected with a shroud of anonymity, the study found.

Most recently, IntSights has found the most active forums for rogue insiders include Dark Money, a forum for buying and selling stolen banking information; cc, a Dark Web site; and exploit.IN, a popular Russian Dark Web forum, she says. Genesis Market, Joker's Stash, and Bitify are among some of the underground markets where stolen bank cards can go for anywhere from $30 to $50 apiece, or $95 for "fresh" cards, for example, Wright says.

What's unclear, however, is just how these employees gone bad access the information they steal and monetize. "It looks like they already have access to it in their jobs, whether they are supposed to or maybe they have admin access they are not supposed to have. ... We're not really sure how they got the access," she says. "But they are definitely out there and in some certain regions, like Russia, they are pretty blatant and open about what company they work for. They're not even trying to hide it."

That openness is not the case in English-speaking forums, however, where rogue insiders and sellers are more cautious and suspicious of buyers and questions. "In English-language forums, they tend to be a lot more cautious and suspicious," especially now that they are aware of researchers and law enforcement infiltrating their spaces, she says. And because law enforcement has been shuttering some of these forums over the past couple of years, it's harder to track where the rogue insiders go next, notes Wright, who will present some of IntSights' latest Dark Web findings at Black Hat Europe in London this week.

But identifying in the Dark Web just who's behind what and from where it came isn't necessarily always cut and dried. There are plenty of cybercriminals selling data they have stolen from their victims.

"The economy of scale of the Dark Web has a multitude of participants — not all of them full-time cybercriminals," notes Tom Kellermann, head cybersecurity strategist for Carbon Black, now part of VMware, which has seen an increase of 41% in so-called "island-hopping," where attackers pivot from one victim to its business partners or other connected targets to steal information.

"The challenge is determining whether these are true insiders or digital insiders commandeering the digital transformation of the corporation and using it to island-hop and access-mine" data, he says.

Finding Out the Hard Way
IntSights gets hired by organizations to drill down on their stolen data in the Dark Web. They often don't have visibility into their data leaking out of the organization, Wright notes. "A lot of organizations are very aware of what's going on in their networks and what's attacking them [and going on] inside, but they aren't aware very much of what is exposed ... outside of their network," she says.

Organizations already are flooded with security incidents on a daily basis, often with an understaffed security team, so they triage the main threats first. "They start with the closest targets and biggest threats first," Wright says. "First, it's malware and data loss, and then if you mature your organization to a point where you can afford an insider-threat team, it's usually one person. Then they are overwhelmed once they start digging into the insider threat."

Rogue insiders are not the most common form of insider threat, of course. Human error is much more common - clicking on a phishing attachment, for example. "Rogue insiders are a strong component of enterprise data loss. End users or administrators with malicious intent are capable of digital vandalism- destroying valuable intellectual property, trade secrets and valuable work data in seconds, with the click of a button," says Garth Landers, director of product marketing for archiving at Mimecast, which today released a report on data loss in financial firms. 

Landers, who notes that human error is much more common, says the threat of rogue insiders requires a strong governance strategy to protect from data loss.

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