The nuisance posed by Flash-based games and Internet viral advertising is now so significant that security vendor SmoothWall has decided to offer a web filter capable of ‘intelligently' blocking the application.

Designed to upgrade the feature set of the company's software-based Network Guardian or SWG-700 hardware appliances, the filter will this week be offered as part of a Feature Pack update to current customers.

According to SmoothWall, the company developed the feature to cater to organisations wishing to minimise the impact from time-wasting Flash viral campaigns that populate the Internet but also Flash-based games. The education sector, in particular, had worries about the content that was being distributed using this channel.

Implementing the filter in a security gateway also allowed admins to control the app without having to ban it outright so internal and legitimate use of Flash - on a company's own websites, say - could still be allowed. Hitherto, the only option has been to block it completely.

Although SmoothWall chose not to emphasise the point, it is also true to say that Flash programs have had more than their fair share of security vulnerabilities which rely on persuading users to access specially-crafted content. This sort of filtering could in principle block such actions if the filtering was able to analyse the behaviour of the app.

"We can also identify a number of different flash applications (including malformed flash files) and we hope to include more categories as the technology matures," said SmoothWall's official release after acknowledging the considerable challenges posed in separating legitimate uses of Flash from non-legitimate or malevolent.

"Game site operators are now going to increasing lengths to hide sites and offer users more ‘discreet' ways to play. Determined gamers have also learnt how to outsmart school filters with less obvious searches (such as searching for just swf) and by embedding their favourite flash games into legitimate looking sites," said SmoothWall.

Rarely does a month goes by without a Flash-related vulnerability being reported. In July, Adobe patched 12 knows security holes in the application.