The study, which tested results of popular keyword searches on Google, Yahoo, Microsoft, AOL and Ask.com, showed that on average, 8.5 percent of sponsored links led users to "risky" sites.
By way of comparison, the study revealed that only 3.1 percent of "organic" or natural results linked to potentially malicious sites.
Ask.com had the dubious distinction of having the highest number of problematic results, with 6.1 percent (sponsored and organic combined).
Google and AOL were next, with 5.3 percent, followed by Yahoo at 4.3 percent and MSN bringing up the rear at 3.9 percent.
Shane Keats, market strategist at SiteAdvisor, told internetnews.com that he hoped this study will be a catalyst for search engines to do more to police their results.
"Search engines have made some efforts to vet their advertisers," he said. "One takeaway that I hope comes out of this study is that search engines do more to protect consumers."
Yahoo responded by saying in a statement that it is, "continually enhancing the search experience it delivers to users."
Yahoo also noted that it offers users "an anti-spy tool to help them identify spyware and we have proprietary technologies and teams of humans worldwide that are dedicated to improving the quality of our ad listings."
Likewise, Ask.com provided internetnews.com with a statement assuring users that "when we identify potentially unsafe results, including organic and paid listings, we aggressively remove them."
One of the most well-known efforts already under weigh is the Strider HoneyMonkey Project run by Microsoft, which is an attempt to ferret out sites that exploit browser vulnerabilities by installing malware (define) on the computers of unsuspecting consumers.
Both Yahoo and Google also require that any advertisers selling pharmaceuticals belong to the SquareTrade Pharmacy Program, which verifies that the sites are actual pharmacies in good standing.
But many experts believe that search engines face an almost insurmountable task in vetting their advertisers.