The malvertising phenomenon is not a new thing; it has been a criminal tactic for over a decade. Back in 2004, visitors to the technology website, “The Register” were hit by a rogue advertisement, which took advantage of a zero-day vulnerability in Internet Explorer to push the BOFRA malware. Over the course of the last decade, many high profile websites have, through their advertising networks been the unwitting routes to market for enterprising online criminals. Victims include the New York Times, Google and the Huffington Post among innumerable others.
Over the years, malvertising has become a very prevalent example of how criminals increasingly subvert legitimate frameworks to spread their malicious creations and to earn an illicit income. The nebulous nature of the online advertising ecosystem makes it all too easy for an attacker to pass unnoticed among all the genuine advertisers, and the global reach of the larger online advertising networks serves to amplify the potential audience for any given attack, way beyond that which the criminal could hope to address unaided.
According to figures released by the Online Trust Alliance, almost 10 billion ad impressions were compromised by malvertising in 2012 and went on to increase by 225% from 2012 to 2013 to more than 209,000 incidents, generating more than 12.4 billion malicious ad impressions.
Users have steadily been moving away from exposure advertising material where possible in both online and traditional media. If the trend of abuse of advertising networks continues then we can expect to see browser makers directly incorporating the ad-blocking functionality, which is today only available as 3rd-party plug-ins. This would decimate the business model for online advertisers. The only potential means of averting this sea change is if advertising networks step up their game when it comes to the verification of both the content they serve, using pre-release sandboxing for example, and the security of their own infrastructure, securing against vulnerabilities that allow the criminals to insert themselves into the ecosystem, vulnerabilities both in technology and in process, for example the effective authentication of the customers that they serve.
To discover more about the impact of malvertising in 2015, have a look at our 1Q 2015 Security Roundup, “Bad Ads and Zero Days: Reemerging Threats Challenge Trust in Supply Chains and Best Practices.”
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