Secure file delete utilties

Matthew

Touchdown! Greaser!
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Matthew
An older guy I know, retired CPA, asked me today about wiping data off hard drives. He has some financial data on his hard drive and wants to make sure it's gone forever. I'm assuming it's a PC (I forgot to ask) and not a Mac. I don't know the OS. I'm going to try to find that out later today or early this week.

What's a good, solid, easy to use utility that can wipe individual files, groups of files, or whole directories? I'm hoping it's something that's easy to install and pretty self explanatory to use.

It's been a long time since I've done any research on these things.
 
Only partially kidding. It’s the only guaranteed way C0E42AB7-D821-46CD-99F3-F3B190744D50.jpeg
 
Only partially kidding. It’s the only guaranteed way View attachment 103359

He just approached me today and said, "If I die, I don't want that information getting out there." The first thing I suggested was the sledgehammer of deletion.

--

I didn't tell him that I have a note next to my DNR order: "Delete my browser history!"
 
For Windows there are many apps, but this might work better:

https://www.techadvisor.com/how-to/windows/how-securely-delete-files-in-windows-10-3675546/

How do I permanently delete a file?

Not many people know this, but Windows has its own built-in secure deletion tool called Cipher that's been present since Windows XP came out. If you prefer not to download any third-party software, this is going to be the best method for you. And while we're using Windows 10 here, it works on all versions back to XP.
 
For Windows there are many apps, but this might work better:

https://www.techadvisor.com/how-to/windows/how-securely-delete-files-in-windows-10-3675546/

How do I permanently delete a file?

Not many people know this, but Windows has its own built-in secure deletion tool called Cipher that's been present since Windows XP came out. If you prefer not to download any third-party software, this is going to be the best method for you. And while we're using Windows 10 here, it works on all versions back to XP.


That might be the trick for this guy - nothing to install, just need to find it.

edit:

I just looked at that. Looks like it's a powershell utility. I'll probably have to talk him through it, but that shouldn't be too bad.
 
Define "Secure".

There's secure against things finding it in the freelist, but if you're "spy level" secure, as pointed out, short of physically destroying the drive, you've got no guarantee that they could find even overwritten data if we're talking magnetic media. Digital data is rather resiliant.
 
For values of classification levels, multiple overwrites of rotating media is sufficiently secure.

Last I knew, contimanated SSDs are destroyed - no way to scrub off classified information.
 
I'd start off by taking it to the range and putting a bunch of rounds through it. It wouldn't delete the data, but it would make it darned hard to read.
 
Power drill, hammer and welding torch. Spinny drives are so last Century...
 
Power drill, hammer and welding torch. Spinny drives are so last Century...
I open up the drive casing, remove the shiny disks, clamp one end in a vice and bend the other one over.

Short of nuking it from orbit, physical destruction is the only way to be sure.

Ron Wanttaja
 
I’m kinda liking the MS Cipher built-in utility (haven’t tried it yet). It overwrites unallocated areas on the drive. So it requires you to delete files first. Other utils delete and then scramble the space used by that file; I haven’t seen any of them claim to destroy files that were already deleted.
 
We used to send mechanical disks to an erasure service for zeroing. Now they go to a certified shredder.

either way comes with a certificate of destruction for records.
 
I'd ask him if he's required to comply with any sort of federal or state regulation for destroying the files. If so, it's likely that physical destruction of the drive is the only acceptable method. Sometimes a full disk secure wipe utility will suffice. File or OS level wipes aren't recognized by any standard that I know of. It's just too easy for them to miss something.

For destruction of a spinny drive, shredding or melting work. It used to be pretty easy to take a drive apart. You'll need little torx drivers, and be careful not to pinch your fingers on the magnets. Keep those, they're handy.
 
I'd ask him if he's required to comply with any sort of federal or state regulation for destroying the files. If so, it's likely that physical destruction of the drive is the only acceptable method. Sometimes a full disk secure wipe utility will suffice. File or OS level wipes aren't recognized by any standard that I know of. It's just too easy for them to miss something.

For destruction of a spinny drive, shredding or melting work. It used to be pretty easy to take a drive apart. You'll need little torx drivers, and be careful not to pinch your fingers on the magnets. Keep those, they're handy.
Hadn’t thought about any regulatory issues. I’ll probably see him next week and ask him about it. There’s a commercial shredder operation near me that give a certification of destruction, or whatever it’s called.
 
Cutting torch and a few fire bricks. Just for the satisfying experience and the 'whoosh' when you push the oxygen lever. Plasma cutter should work too.
 
I've used Bitraser as a gov approved software tool before. It meets DoD 5220.22 and some other big NSA standards I can't recall immediately.

Good enough for un-class USAF, probably good enough here too. Licenses aren't free, but probably not too bad if he's serious about destroying data.
 
I think federal unclassified is based on NIST 800-53, in general, and that's a pretty good standard. For good or bad, some federal agencies are still allowed to promote their own standards, FBI with CJIS, which is pretty good, and IRS with pub 1075, which is both pedantic and dated. No idea if the OP's friend is subject to any of this. My point is just that common sense doesn't always apply with these standards.
 
Written by a certified genus, Mark Russinovich, who was lured away from Austin when Bill G offered him a dump truck load of gold coins to move to Redmond to teach his developers to write windows apps, the best delete utility:

https://docs.microsoft.com/en-us/sysinternals/downloads/sdelete

All of the free System Internals utilities are best in class.
 
I did some criminal computer forensics for LE.... trust me, it's hammer*-time.

Jim

* or equivalent
 
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I'd start off by taking it to the range and putting a bunch of rounds through it. It wouldn't delete the data, but it would make it darned hard to read.

This is what I do. I don’t think I’m yet enough of an NSA target for them to dig it out of my trash and try to read what’s left.
 
Last night I ran some options past his son. He’s going to check on his dad in the next couple days. I’ll find out then if he even uses that PC anymore. If not, then, yeah, that drive will soon be in many little pieces.
 
I like to pop them open & dig the magnets out first. They're fun to play with and great for holding the kid's artwork to the gunsafe.
IMG_20220103_105709255.jpg
 
I did some criminal computer forensics for LE.... trust me, it's hammer*-time.

Jim

* or equivalent
Might be good stress relief. Put the disk in a vise, then beat it into a taco shape. Or use a big vise-grip pliers and get some isometric exercise. Never tried taking one to the range. Guess a 5.56 might do the trick, dunno. Use a full magazine on it going "yeeeHAH!"
 
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Might be good stress relief. Put the disk in a vise, then beat it into a taco shape. Or use a big vise-grip pliers and get some isometric exercise. Never tried taking one to the range. Guess a 5.56 might do the trick, dunno. Use a full magazine on it going "yeeeHAH!"

better to use bullets that are designed to expand rather than ball ammo.
 
better to use bullets that are designed to expand rather than ball ammo.
Biggest thing I've got in that category is .45 ACP. Need to break in a new Kimber, anyway. Had to have something after that unfortunate boating accident. Anybody got a disk they want perforated?
 
Biggest thing I've got in that category is .45 ACP. Need to break in a new Kimber, anyway. Had to have something after that unfortunate boating accident. Anybody got a disk they want perforated?

They look pretty cool with the holes blown in them.
 
Go big or go home...

signal-2022-01-03-180338_001.jpeg

In all seriousness, drives at my current office usually get taken out to the gun range over an extended lunch. If that's not convenient, I open the drive case, pour fine-grain beach sand into the drive and plug it in and let the sand do its work on the platters.
 
I learned that shooting disks full of holes was the preferred method to render them unreadable way back in grad school.

Interestingly, we tried holding floppies up against the big (300 MHz was what we had at the time) NMR magnets--this before the magnets were shielded, and the external field was quite strong--and found it either didn't erase data at all, or only caused minor corruption.
 
That would be correct. I'm not too worried about hard drives being readable after an encounter with one of these.

@GaryM : I've tried playing with magnetic tape and floppy disks and MRI machines and it's surprising how resilient magnetic media is. I always made it a habit of erasing my driver's license mag stripes with bulk erasers over the years. My state's most recent IDs use barcodes only, which can be foiled with some heavy amounts of pressure and friction.
 
I learned that shooting disks full of holes was the preferred method to render them unreadable way back in grad school.
I tried that but the bullets just kept going through that little hole in the middle. :p
 
I like the range idea ... or give it to my ex-girlfriend. She can totally destroy anything. :happydance:
 
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