1. Solutions to Secure File Deletion
By: Jonathan Charlton
IASP DLA

2. Ignoring Secure File Deletion
For a second, let’s assume that you were hosting confidential files on a USB until you were given a new company laptop.
You delete the files on the USB after they have been copied over to the laptop and you give the USB to someone else because you don’t need it anymore.
Anyone that finds that USB can recover those files and gain access to your confidential information.
While this may seem like an issue that does not happen often, even one instance of this occurring could compromise an entire network.
Once a network is compromised because of your files being recovered, there is a high likelihood you are the one that will take the fall for it.

3. How Are These Files Recovered?
The same company that provides you the tools to securely delete files from your devices, also has a tool that can recover the files you do not securely delete.
Recuva is a file recovery tool that scans the space on your hard drives for the remains of files that have been deleted through methods that are not secure.
In the best case scenario for a malicious user, the files will exist without being overwritten at all. In the worst case the files will be partially overwritten or completely unrecoverable.
How can you protect yourself from your lost or stolen data being recovered?

4. Priority Number One CCleaner
CCleaner from software Developer Piriform is shipped as software meant to be used to clean up your computer’s unused or temporary files, as well as internet history, cookies and your registry.
The program also comes with a tool to wipe your hard drive’s “free space” to securely delete any files that you may have previously removed from your computer.
If the drive may be compromised at any point and you have knowledge of this ahead of time, you can also wipe the entire drive so that there is no remaining files, just a sea of 1’s and 0’s that mean nothing.

5. Priority Number Two
While completely wiping your drive(s) with CCleaner multiple times leaves you with a drive that previously deleted data will be almost unrecoverable, for the more security inclined drive destruction will be a much safer method for protecting data.
A common practice in government agencies, completely destroying a drive is the guaranteed way that no one will recover your data.
In the event that you need to fully destroy a drive you are probably handling data that is too confidential for a normal end-user and you will have more confidential file deletion methods and proprietary programs not available to the public.