Researchers regularly see malicious ads in search results representing themselves as coming from legitimate businesses and organizations. Whether it’s a regional municipality, a utility like a power company, or a big business, people will use search engines simply to pull up the URL of an organization. And if the first results or the most convenient results to click on are ads, scammers have the opportunity to buy this real estate.
“The volume of these things is immense,” says Sean Gallagher, the senior threat researcher at Sophos. “Search engines like Google will say they check the content of ads to ensure they’re safe, but the thing is that attackers are using ad delivery networks and can redirect the URL after the ad is paid for.”
Google is clearly aware that malicious ad activity is growing and evolving. The company specifically addresses misleading and fraudulent ad activity in its policies, including a “misrepresentation policy,” and says that it takes numerous approaches to vetting ads and detecting malvertising. Attackers have continued to develop circumvention methods, though, to avoid having their ads flagged or removed. In 2023, Google blocked or removed about 5.5 billion ads and suspended more than 12.7 million advertiser accounts.
The company has also taken steps over the years to label ads clearly and delineate them in the search results layout. Still, any search engine that’s supported by ads ultimately has the two types of content side by side, especially on mobile where users have limited screen space.
“We expressly prohibit ads that attempt to circumvent our enforcement by disguising the advertiser’s identity to deceive users and distribute malware,” Google spokesperson
Nate Funkhouser told WIRED in a statement. “When we identify an ad that violates this policy, we remove it and suspend the associated advertiser account as quickly as possible.”
Sophos’s Gallagher points out that criminals can often get the most for their money when buying ads for more unique searches, where they can dominate the ad space and get to the top of the results more organically. But both Sophos and Malwarebytes researchers also regularly see malicious ads running against frequent searches like those for Google, Walmart, Disney+, Slack, Lowe’s, and Apple. Segura even says that Malwarebytes itself has to invest heavily in buying search engine ads just to keep malvertising at bay for the company’s brand.
“We have to defend our brand so much,” he says. “People take advantage of that.”