Online advertising firm Sizmek Inc. [NASDAQ: SZMK] says it is investigating a security incident in which a hacker was reselling access to a user account with the ability to modify ads and analytics for a number of big-name advertisers.
In a recent posting to a Russian-language cybercrime forum, an individual who’s been known to sell access to hacked online accounts kicked off an auction for “the admin panel of a big American ad platform.”
“You can add new users to the ad system, edit existing ones and ad offers,” the seller wrote. The starting bid was $800.
The seller included several screen shots of the ad company’s user panel. A few minutes on LinkedIn showed that many of these people are current or former employees of Sizmek.
The seller also shared a screenshot of the ad network’s Alexa site rankings:
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A screenshot of the Alexa ranking for the “big American ad network,” access to which was sold on a cybercrime forum.
I checked Sizmek’s Alexa page and at the time it almost mirrored the statistics shown in the screenshot above. Sizmek’s own marketing boilerplate says the company operates its ad platform in more than 70 countries, connecting more than 20,000 advertisers and 3,600 agencies to audiences around the world. The company is listed by market analysis firm Datanyze.com as the world third-largest ad server network.
After reaching out to a number of folks at Sizmek, I heard back from George Pappachen, the company’s general counsel.
Pappachen said the account being resold on the dark web is a regular user account (not a all-powerful administrator account, despite the seller’s claim) for its Sizmek Advertising Suite (SAS). Pappachen described Sizmek’s SAS product line as “a sizable and important one” for the company and a relatively new platform that has hundreds of users.
He acknowledged that the purloined account had the ability to add or modify the advertising creatives that get run on customer ad campaigns. And Sizmek is used in ad campaigns for some of the biggest brands out there. Some of the companies shown in the screenshot of the panel shared by the dark web seller include PR firm Fleishman-Hillard, media giants Fox Broadcasting, Gannett, and Hearst Digital, as well as Kohler, and Pandora.
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A screenshot shared by the dark web seller. Portions of this panel — access to a Sizmek user account — was likely translated by the Chrome Web browser, which has a built-in page translate function. As seen here, that function tends to translate items in the frame of the panel, but it leaves untouched the data inside those frames.
Crooks who exploited this access could hijack existing ad campaigns running on some of the world’s top online properties, by inserting malicious scripts into the HTML code of ads that run on popular sites. Or they could hijack referral commissions destined for others and otherwise siphon ad profits from the system.
“Or someone who is looking to sabotage our systems in a bigger way or allow malicious code to enter our systems,” Pappachen offered.
Pappachen said Sizmek forced a password reset on all internal employees (“a few hundred”), and that the company is scrubbing its SAS user database for departed employees, partners and vendors whose accounts may have been hijacked.
“We’re now doing some level of screening to see if there’s been any kind of intrusion we can detect,” Pappachen said. “It seemed like [the screenshots were accounts from] past employees. I think there were even a couple of vendors that had access to the system previously.” Continue reading