Researchers at Cisco spotted a recent malvertising campaign where victims were redirected by ads on the AppNexus network to sites hosting the Angler Exploit Kit and exploits against Silverlight vulnerabilities. Silverlight, similar to Adobe Flash, is Microsoft s plug-in for streaming media on browsers. A recent campaign spotted by researchers at Cisco spiked between May 7 and May 13, accounting for as high as 18 percent of the total HTTP requests for sites hosting Angler sites. The kit also hosts exploits for Flash and Java, though none of the Java exploits have been triggered.
Source: https://threatpost.com/malvertising-redirecting-to-microsoft-silverlight-exploits/106158/