Secure hard-drive data wiping
Date: 25 Jan, 2012
Posted by: admin
In: hints & tips|linux, open source & software|recycle
How to securely delete data from a hard-drive (or USB pendrive) so that the information is virtually unrecoverable even to someone with unlimited funds.
Myth: Over-written hard-drive data can be [easily] recovered
It’s easier to guess the data than recover it!
Over-write it and then smash it with a hammer?!?
“If you are bloody minded, hard-drive data can still be read off the platters since the smashing will not completely destroy the magnetic domain information.”
(Friend-of-a-friend on Facebook)
Sorry but this just isn’t true. The success rate of restoring data from a full zero-pass (setting all bits to zero) is so low and the cost so prohibitive that no-one would attempt it without expecting a multi-million dollar return. This used to be almost feasible but on a modern drive the magnetic domains are so tiny …
“The fallacy that data can be forensically recovered using an electron microscope or related means needs to be put to rest.”
(Wright, et al., “Overwriting Hard Drive Data: The Great Wiping Controversy” [online viewer])
Of course if you’re an active secret agent harbouring data that can bring down a super-power then you’d use a hidden encrypted partition (on a USB pendrive) and then just thermite the drives for speed and certainty.
