Nearly half (46%) of the Alexa top one million websites were found to be risky, putting businesses at risk as their users visits these sites.
The finding is part of a new report published by Menlo Security entitled "State of the Web 2016: Quantifying Today's Internet Risk," where researchers examined key characteristics of the top one million websites, as ranked by Alexa, to determine sources of risk.
Last year, Menlo's "State of the Web" report highlighted two key findings: One in three domains in the Alexa top 1M were deemed risky, and one in five ran vulnerable software.
This year, Menlo focused on Alexa's top 1M websites but factored in the 25M background-initiated requests a browser makes when visiting any of the primary 1M sites. When users access top Web destinations, they unknowingly make millions of other requests.
"When you go to a site, your browser goes to 25 other sites," says Menlo Security CTO Kowsik Guruswamy.
Background sites provide active content to the browser for content delivery, ad delivery, trackers, and beacons. Researchers evaluated factors that could affect the primary websites' risk, such as release dates, software version, CVE IDs, and third-party risk intelligence.
Menlo considers a site risky if its homepage or associated background websites is running vulnerable software; if it's a known-bad; or if it had a security incident in the last 12 months. Guruswamy notes the 46% risk is a "pretty significant number."
According to there report, there are three main reasons behind the growth of Web exploitation: websites are easier to exploit, traditional security products don't provide sufficient protection, and phishing attacks can now use legitimate sites.
Outdated technology is a big factor, Guruswamy says. Thousands of Web servers are using out-of-date software, and the underlying background domains serving ads are vulnerable to exploit kits used to deliver malware. Users surfing the Web are putting themselves at risk for attack.
"The risk factor has never been easier to exploit because people are running really old software," he says. Vulnerable software was the leading factor in classifying a website as risky by a factor of more than two, and researchers found the oldest vulnerable software in the top 1M sites was launched in the year 2000.
Looking at a breakdown of site categories, news and media websites were at the greatest risk, with 50% being classified as risky. Business and economy websites had the most recent threat history.
"If you look at websites with security incidents in the last 12 months, business and economy is at the top," Guruswamy notes. "That's surprising, and bad for enterprises, because many organizations have a general assumption that if a site is popular, it's okay for users to go to. Turns out, that's not the case."
Businesses are aware of the problem, he continues, but there is little concern about where malware starts. The existing technologies companies are using to secure themselves don't address the problem.
Security pros struggle to come up with a solution. They could implement a comprehensive solution by blocking all uncategorized websites, but then they face complaints from end users trying to access them.
"IT is caught in the middle," explains Guruswamy. "If they block [sites] they're the bad guys; if they allow them, then they run the risk of infection."
The challenge won't go away in 2017, when the risks of malware, ransomware, and credential theft will continue to target employees and businesses. Security products will be in the middle, trying to figure out if supposedly legitimate websites are safe, he says.
Guruswamy says businesses, website owners, and end users need to work together to stay safe. Enterprise IT administrators should explore the possibility of isolation as a key way to prevent security problems, a strategy he says has been adopted at JPMorganChase. Users who click links within emails are taken to an isolation platform that runs a browser on their behalf.
"We've lost the privilege to connect to the Internet directly," he notes. "Businesses should start thinking about isolation as a means of making the problem go away."