Last month KrebsOnSecurity published research into a large distributed network of apparently compromised systems being used to relay huge blasts of junk email promoting “online dating” programs — affiliate-driven schemes traditionally overrun with automated accounts posing as women. New research suggests that another bot-promoting botnet of more than 80,000 automated female Twitter accounts has been pimping the same dating scheme and prompting millions of clicks from Twitter users in the process.
Not long after I published Inside a Porn-Pimping Spam Botnet, I heard from researchers at ZeroFOX, a security firm that helps companies block attacks coming through social media.
Zack Allen, manager of threat operations at ZeroFOX, said he had a look at some of the spammy, adult-themed domains being promoted by the botnet in my research and found they were all being promoted through a botnet of bogus Twitter accounts.
Those phony Twitter accounts all featured images of attractive or scantily-clad women, and all were being promoted via suggestive tweets, Allen said.
Anyone who replied was ultimately referred to subscription-based online dating sites run by Deniro Marketing, a company based in California. This was the same company that was found to be the beneficiary of spam from the porn botnet I’d written about in June. Deniro did not respond to requests for comment.
“We’ve been tracking this thing since February 2017, and we concluded that the social botnet controllers are probably not part of Deniro Marketing, but most likely are affiliates,” Allen said.
ZeroFOX found more than 86,262 Twitter accounts were responsible for more than 8.6 million posts on Twitter promoting porn-based sites, many of them promoting domains in a swath of Internet address space owned by Deniro Marketing (ASN19884).
Allen said 97.4% of bot display names had the pattern “Firstname Surname” with the first letters of each name capitalized, and each name separated by a single whitespace character that corresponded to common female names.
The accounts advertise adult content by routinely injecting links from their twitter profiles to a popular hashtag, or by @-mentioning a popular user or influencer on Twitter. Those profile links are shortened with Google’s goo.gl link shortening service, which then redirects to a free hosting domain in the dot-tk (.tk) domain space (.tk is the country code for Tokelau — a group of atolls in the South Pacific).
From there the system is smart enough to redirect users back to Twitter if they appear to be part of any automated attempt to crawl the links (e.g. by using site download and mirroring tools like cURL), the researchers found. They said this was likely a precaution on the part of the spammers to avoid detection by automated scanners looking for bot activity on Twitter. Requests from visitors who look like real users responding to tweets are redirected to the porn spam sites.
Because the links promoted by those spammy Twitter accounts all abused short link services from Twitter and Google, the researchers were able to see that this entire botnet has generated more than 30 million unique clicks from February to June 2017. Continue reading