Last week, I wrote a bit about my discovery of exactly how easy it is to recover data that has been deleted from a hard drive. After realizing that all the data I’ve ever deleted is just a click away, I tried to find a way to make the deletions more secure. The solution I came up with was to store data on an encrypted disk image and delete that. I posted my solution on my Lifehacker blog, where a helpful commenter pointed something out to me:
Why not just use a secure delete program that overwrites the deleted data with various patterns? Your technique does not guarantee the original file is properly deleted. I get it that the copy bec of the image will be scrambled, but not necessarily the original. Anyway, your technique seems quite a Rube Goldberg approach and a probably insecure one at that. Many secure delete programs can also shred free space.
This person is, of course, correct. What makes matters worse is that I was already aware of these secure delete programs. But this was a case where I was so involved in what I was doing that I couldn’t see the forest for the trees. A little investigation revealed that Mac has a built-in secure delete program. So any data recovered from my drives is my own fault. Lesson learned.
This is just another one of those things that I wrote about last week. People need to interact with your work for you to start to see how sound it really is. That commenter was merely another iteration of my dog escaping from her new house. This more recent blunder was certainly a bit embarrassing, but I’m glad I put my ideas out there. In this case, I came up with a really roundabout way of doing a fairly standard action, but I still learned something valuable from it. How many times have I done that and had no idea about it?