April 4, 2024 By Jérôme Segura

Most of the malicious search ads we have seen have originated from Google, but threat actors are also abusing other search engines. Microsoft Bing is probably the second best target due to its close ties to the Windows ecosystem and Edge browser.
In this blog post, we look at a very recent malvertising campaign impersonating the popular VPN software NordVPN. A malicious advertiser is capturing traffic from Bing searches and redirecting users to a decoy site that looks almost identical to the real one.
The threat actors went ever further by trying to digitally sign a malicious installer and hosting it on Dropbox. Victims will have the impression they are getting NordVPN as it is part of the package, but will also inadvertently install a Remote Access Trojan known as SecTopRAT on their computer.
We have reported the malicious Bing ad to Microsoft, and other parts of the distribution infrastructure to their respective provider. We want to reiterate that NordVPN is a legitimate VPN provider and they are being impersonated by threat actors.