If you rely on Software Update to fetch all the security updates you need, think again.

Sure, it's a convenient way of installing updates delivered by Apple if you've only got one or two systems to manage, but it's not the whole story.

Earlier this week, Microsoft and Adobe released multiple security updates, and it's almost certain that you'll need to download and install at least one of them.

Microsoft first: the headline update is for Office. Microsoft AutoUpdate will probably grab that for you, providing it hasn't been disabled. But look carefully if you have both Office 2004 and 2008 installed - on my system, it only updated one of them. Nor did Microsoft AutoUpdate fetch the updated version of Silverlight for me.

You can find the Office 2004 11.6.0 and Office 2008 12.2.6 updates, plus Open XML File Format Converter for Mac 1.1.6 (for Office 2004 and v.X) via Microsoft's Mac downloads page. To get the latest version of Silverlight, click here.

Now Adobe: you can get the new version of Flash Player here, and if you've previously installed AIR the latest version is here.

It shouldn't be this difficult. I'm almost coming round to the point of view that security patches should just happen automagically, much as they do with Chrome. But I would like a 'wait 24 hours before applying patches' preference, just to give other people a chance to be guinea pigs - but if we all did that...

But some vendors (eg Symantec) do something similar already, by pushing updates to an initially small subset of customers, and them widening the distribution if no problems are seen.