Wow talk about old!
I remember this being demo'ed back in 2004!
For reference, when this hack came about the ipod 3G had just come out!
It works on any OS with DMA enabled via firewire, including Linux/OSX. Used to unlock peoples WinXP machines by using the FW port. Their faces were priceless!
Anyway, this was by design. Any bus that allows DMA (including PCI/cardbus/pcmcia) allows this hack, and it's been in use for many many years. Firewire made it easier due to the plug and play nature, but it wasn't new.
Despite this though, we still used fw for ages (still do actually) because of it's lower overhead and it's DMA capability.
The same thing that allows this hack allows remote DMA (accessing the contents of RAM from one machine on another remote machine). This was pretty much the preserve of infiniband supercomputers with skyhigh prices to match. The fact we could do the same thing for about 50 quid using firewire more than made up for this security hole. Built our uni cluster using this feature.
Such a shame it never caught on as well as USB though. I hear that thunderbolt offers the same DMA features* (also being bus based interconnect) makes me happy. The idea of a 10gbit/s interconnect at consumer prices for the next cluster I build sounds awesome!
Remember one thing about security. If your attacker has physical access that's the end, they can get in.
*Note: Newer processors are developing what is being called an IOMMU, which will control/protect certain areas of memory from being altered or read by external devices, which should actually put a stop to these attacks. The older processors did not offer this, so were vulnerable to this attack.
If done correctly thunderbolt will not have this security hole, while offering similar features and a lot of speed. What's not to like?