Block malvertising

Many instances of ransomware are delivered through malicious advertising — or ‘malvertising’. This is the process of injecting malicious malware-laden ads into legitimate online advertising networks and webpages — since 2012, billions of ad impressions have been hijacked, including trusted sites. This malware gets through defences, and can silently infect users’ systems — no interaction required.

So how do you protect against these ads? Your anti-malware software should have some protection — both Norton and the Premium version of Malwarebytes have defences against malicious websites built in, and you’ll see a steady stream of alerts as sites are blocked, not just from your browser, but other apps, such as Skype, too.

Make sure you’re running the latest version of your browser and Adobe Flash, as some malvertising targets vulnerabilities, as we discussed in the ‘Importance of Being Updated’ box (page 45). Speaking of which, setting Flash to run only on your say-so is a good idea, as encouraging advertisers to stop using Flash for their ads is one way to improve security going forward.

There’s also an argument for avoiding dangerous websites, where these kinds of ads (as well as other unwanted popups) tend to proliferate — use your WOT or Norton Safe Web browser plugin to steer clear.

Perhaps the most effective way to protect against malvertising is through ad-blockers, which block all ads that aren’t expressly allowed. Norwegian browser Opera ( www. opera.com) is the first to provide ad-blocking natively — no plugins required. Alternatively, install the AdBlock Plus plugin ( https://adblockplus.org), which works with all major browsers and is open-source. Be sure to whitelist trusted (and responsible) sites, though, as adverts are the lifeblood of many, enabling them to distribute content for free.