Online users are likely to run into at least one malicious advertisement every week, according to data released by RiskIQ, a threat management firm.
In its 2016 Recap report, the company found that malvertising increased in eight of nine categories tracked by the firm, with an overall increase of 132 percent compared to the previous year. Of the nearly 2 billion pages, the company found 7.6 million fraudulent or malicious advertisements.
“Every indication that we have is that malvertising is increasing on all fronts,” Ian Cowger, a security researcher at RiskIQ, told eWEEK. “It is a problem that affects every step in the advertising chain and each one of them shares the responsibility.”
Malicious online advertisements represent an effective way for cybercriminals to infect victims’ systems, because the distribution medium allows the attackers to reach millions of people using advertisements as a stealthy vector of infection. In July, for example, security firm Proofpoint found that a malvertising operation known as AdGholas had likely redirected 1 million to 5 million potential targets a day to sites that attempted to exploit their computers.
Other malvertising campaigns have attempted to infect users with ransomware using a pop-under ad, so that the victim might not even realize that an advertisement is being shown.
During 2016, RiskIQ used automated systems to check more than 2 billion pages where malicious advertisements are often found. In 0.4 percent of cases—1 out of every 250 pages—the company detected some kind of malicious or fraudulent advertisement.
The most popular type of threats were advertisements that were part of a scam, but a variety of malicious binaries were also detected by antivirus software or a scanner such as VirusTotal. Finally, fake software and redirects were common as well.
The increase was due in large part to improvements to the way that RiskIQ scanned, the company acknowledged. After adding better machine learning to detect scams, for example, the detection in that category climbed by a factor of nearly 20.
“It drastically increased our ability to detect these scams,” Cowger said.
Ad blockers are an effective way to stop malvertising, but the technology also prevents publishers from garnering revenue and providing content for free and so has become controversial. In 2016, some 70 million Americans were expected to use an ad blocker, according to RiskIQ’s report.