Posted by Virus Bulletin on Aug 28, 2014
If you do need to run plug-ins, make sure you enable click-to-play.
Last week, we published a blog previewing the VB2014 paper 'Optimized mal-ops. Hack the ad network like a boss' by Bromium researchers Vadim Kotov and Rahul Kashyap. In the paper, they show how purchasing ad space from legitimate ad servers, and using it to serve malicious ads, gives malware authors a lot more opportunities to spread their malicious creations than exploit kits ever did.
As if the paper didn't make this point strongly enough already, Fox-IT researcher Yonathan Klijnsma has discovered a campaign that served malicious ads on a number of prominent websites, including tmz.com, ibtimes.com and java.com — in all cases, vulnerable users were infected without having to click on the ads.
There is some irony in the malware being served on java.com, as exploits targeting the Java browser plug-in are commonly used to serve malware. Although these days exploit kits tend to focus mostly on Flash and Silverlight exploits, few people actually need the Java plug-in, and uninstalling is much easier than always making sure you have the latest version running. If you do need to run the Java plug-in, at the very least you should take advantage of click-to-play.
As Yonathan points out, there is no silver bullet to protect yourself from malvertising, and he too highlights the importance of click-to-play, as well as uninstalling unnecessary plug-ins and keeping those that are needed up to date.
Posted on 28 August 2014 by Martijn Grooten