Web smut seekers take resurgent Ramnit malware from behind
♪ Botnet knocked down, but it gets up again ♪
Aficionados of salacious smut sites in the UK and Canada are picking up some nasty software that infects systems by using corrupted pop-under adverts.
Security researchers at Malwarebytes Labs running a malware honeypot have started noticing resurgence in the Ramnit trojan among the samples. Ramnit was a particularly pernicious piece of code that specialized in harvesting banking credentials and building a botnet. It was supposed to have been taken down after a 2015 operation by Europol.
Since then isolated cases of infection have popped up, notably in a German nuclear power plant, but now it appears the operators are back in business and they are exploiting one of mankind's oldest urges to spread itself.
The researchers noted that the malware was being spread by redirecting and code-injecting malicious adverts that were posted on the ExoClick ad network. These advertisements pop up under the main browser, making them unlikely to be noticed initially and allowing more time for a successful attack.
"This Traffic Distribution System mostly loads benign adult portals/offers via ExoClick. The actual malvertising incident takes place next with a 302 redirect to a malicious TDS this time, which performs some geolocation fingerprinting and checks the upper referer before loading the RIG exploit kit."
The company has since been in contact with ExoClick, the adverts have been taken down, and new malware signatures have been distributed. But it looks as though Ramnit isn't going away any time soon. ®