Update: Mavericks users can now update to 10.9.2 which fixes the flaw. 🙂
News is just breaking of a flaw in Apple’s implementation of SSL security, which could affect anyone using iOS and 10.9 OSX over public/open access wifi ‘hotspots’.
If you’re using iOS, please ensure you do Software Update immediately as a patch has already been released by Apple.
No word from Apple on OS X at time of writing. You can test to see if you have the problem by clicking the following link. Basically, if SSL is working properly you shouldn’t be able to read the message on this page:
If you can read the message on that website from your Mac computer, the best advice to date is to stay off public/open access wifi networks until we hear something more from Apple.
Ars Technica have more information on the security flaw here.
If you need to flush the DNS cache in Mac OS X, be aware that the commands for this have changed through successive OSs, including Lion.
Flushing the cache is sometimes a good idea if you are unable to reach a site that you know is live but keeps returning an error (you can check whether a site is live for others by typing its address here: Down for everyone or just me?).
You can download my free app FastTasks that will do this (and a whole lot more! 🙂 ) for you without you needing to mess around on the command line. However, if you want to do it manually, then open Terminal (Applications > Utilities > Terminal.app) and use the appropriate command for your operating system:
In Leopard / Snow Leopard
In Lion and Mountain Lion
sudo killall -HUP mDNSResponder
With Lion, you’ll have to follow the command with your Admin password, which will be invisible when you type it.
FastTasks – a utility for common terminal tasks