back to article What do sexy selfies, search warrants, tax files have in common? They've all been found on resold USB sticks

About two-thirds of USB memory sticks bought secondhand in the US and UK have recoverable and sometimes sensitive data, and in one-fifth of the devices studied, the past owner could be identified. These results come this week from a study conducted by the University of Hertfordshire in the UK and commissioned by Comparitech, a …

  1. redpawn Silver badge

    I used to

    shred all my mail. Now I sell it on ebay as recycled paper.

    1. Anonymous Coward
      Anonymous Coward

      Re: I used to

      How many admins get requests to enable USB ports so a file can be transferred?

      Puts it into context...just tell them to email it ha ha.

  2. Ole Juul Silver badge

    Seconhand USB sticks?

    Niche market, I guess. I've never seen anything like that for sale. They're cheap enough new.

    Now if we were talking 1989, then I would have been getting discarded boxes of 5.25" floppies, checking for useful software and reformatting them. Actually that was lots of fun to look at funny resumes and letters to girl friends. Sadly there used to be a considerable number of financial and medical records as well.

    1. Dazed and Confused Silver badge

      Re: Seconhand USB sticks?

      I'm sure I remember reading here, many years back, a posting by someone who'd bought a second hand laptop off eBay only to discover the waste basket full of very intimate photos of the previous owner who was rather well known and her public persona was very different to that shown in the pictures on her old laptop.

    2. big_D Silver badge

      Re: Seconhand USB sticks?

      I thought it was odd.

      a) who is stupid enough to sell a stick they've used? If you don't need it anymore, destroy it. They aren't generally worth much anyway.

      b) who id stupid enough to buy a stick? It is the same principal as finding a USB stick in the carpark, you don't know where it has been, you don't know if it is malicious (simply infected with a virus the seller didn't know about or someone has hacked the controller itself).

      The only, half way, secure way is to buy new, sealed in original packaging sticks from reputable suppliers.

      1. dajames Silver badge

        Re: Seconhand USB sticks?

        a) who is stupid enough to sell a stick they've used?

        It beggars belief, doesn't it?

        I rather assumed that any USB stick sold secondhand would be stolen (and that the original owner would not have been in a position to erase it before sale) ... but I suppose some may cone from house clearances, and the like.

      2. Jamie Jones Silver badge

        Re: Seconhand USB sticks?

        "The only, half way, secure way is to buy new, sealed in original packaging sticks from reputable suppliers."

        I note you say "half way", which is good, because even Amazon now sells fake usb sticks (well, they allow third party suplliers to do so quite openly, and to Joe Bloggs, that's the same thing - after all, it's Amazon you make your payment to.)

        There ought to be a law.... (!)

        Just one of MANY: https://www.amazon.co.uk/AMAZING-Flash-Drive-Memory-Thumb/dp/B07BCXKZCV/

        1. big_D Silver badge

          Re: Seconhand USB sticks?

          And fake processors and and and.

          They were caught in Germany selling fake Intel Core i3-K processors, they were sending out Core i3-8350K fully packaged and it turned out the packaging was a Pentium 4 chip with a sticker on the top saying Core i3.

          They have variously alleged that the supplier supplied the wrong processors or that somebody had bought and returned unopened and it was sent back out (they've been caught a couple of times now).

    3. rdhood

      Re: Seconhand USB sticks?

      "Niche market, I guess."

      Strange. 16G sticks are going for something like 2 for $7 (us) NEW. I guess if they are selling them by the handful for $1.... maybe there is a market.

    4. Jamie Jones Silver badge
      Happy

      Re: Seconhand USB sticks?

      I'd have thought than in 1989, second hand 5.25" floppies were worth the equivalent (taking into account inflation etc.) as second hand usb drives are now..

      Might it just be that now you are earning, the cost is not relatively as high as when in 1989 and you were a kid on pocket money? (I know, I've made a number of assumptions here!)

  3. d3vy Silver badge

    I cant imagine ever feeling the need to recoup the paltry amount that a second hand drive is worth when I've been finished with it - certainly not one which may have contained sensitive data.

    So these stats could also just show that people in the UK are more prone to disposal of their retired drives than resale.

    As for the guy with the nude pictures and the contact details - If that was an accident Ill eat my hat.

    I used to have a side business recycling second hand machines for resale from the local council recycling centre - the amount of home made porn being produced in central Lancashire and left on discarded PCs is astounding!

  4. Alienrat

    Not just USB

    The last laptop (an MS surface) I bought the previous owner had put the copy of their document folder in the bin, but not even emptied it. There was his CV, a scan of his passport, their full photo library, scans and documents related to their mortgage application (nice house), stuff related to their last holiday and internal documents from his girlfriends business. Pretty well everything you need to make a life sold for a few hundred quid. Wasn't the first time I had seen stuff like that but the most complete.

    I thought I could contact them about it (not like I didn't have the details to do so), but what was the point. So I deleted it all and made a note to never be them!

    1. Teiwaz Silver badge

      Re: Not just USB

      made a note to never be them.

      I thought they had a nice house?

      1. Alienrat

        Re: Not just USB

        > I thought they had a nice house?

        Only because I decided to not walk into the bank with the documents I had and transfer it over to myself!

  5. Mr Dogshit

    "There were nude images of a middle-aged man"

    Hey! I want my stick back, please.

    1. Allan George Dyer Silver badge
      Joke

      Re: "There were nude images of a middle-aged man"

      Sadly, there is no way to reverse the ageing process. You'll have to be satisfied with however your stick has deteriorated.

    2. BebopWeBop Silver badge
      Joke

      Re: "There were nude images of a middle-aged man"

      And you could pass me the sick bag at the same time

  6. CAPS LOCK Silver badge

    I bought a used 1TB 3.5 incher off Tatbay...

    ... It had been 'formatted'. Oh how I laughed at all the documents I recovered. I use a hammer to 'format' my used drives.

    1. big_D Silver badge
      Boffin

      Re: I bought a used 1TB 3.5 incher off Tatbay...

      That relieves stress, but Thermite is much more fun!

      1. A.P. Veening

        Re: I bought a used 1TB 3.5 incher off Tatbay...

        Only for a pyromaniac (but we are in a sufficiently large group ;) ).

    2. Omgwtfbbqtime Silver badge

      Re: I bought a used 1TB 3.5 incher off Tatbay...

      That's a waste, there are some good welding magnets in them.

      Not to mention a very pretty coaster to put scalding hot coffee on to.

      (For those that still smoke - the top case makes a good ashtray too)

      1. Anonymous Coward
        Anonymous Coward

        Re: I bought a used 1TB 3.5 incher off Tatbay...

        I made wind chimes out of mine........

        Couple of holes drilled into the platers (watch out for the glass ones!), strung together with wire from a network cable. Tie them to the PCB and on the other end, tie to the motor as a weight.

        Also made a pair of speakers as well

  7. JimmyPage Silver badge
    Pirate

    Who is selling sticks ?

    A great way to kick off a virus or malware epidemic ?

  8. Yorick

    A “single pass doesn’t do it”, this article tells us, and then a little further down that we need a “full, low level format”.

    When even the experts are confused, what chance does a consumer stand?

    For a flash drive, one full format pass will do it. There’s no “lingering magnetic charge” to worry about. Even with modern hard drives, multiple passes sounds more like voodoo than science. To extract anything from a drive that has been fully formatted once is likely impossible. Used to be that wasn’t the case, but the way we write to spinning rust has changed.

    A “low level format” is not so easily achieved with OS tools, though there are utilities for it. All it does for someone over a “full format” is map out bad sectors - that doesn’t make it more secure.

    One full format ought to do it, for flash, ssd, and any hard drive manufactured in the somewhat recent past.

    1. Mystic Megabyte Silver badge

      Photorec

      Maybe you should try this and its sister tool TestDisk. I have used it to recover data after a format and loss of partitions.

      "PhotoRec ignores the file system and goes after the underlying data, so it will still work even if your media's file system has been severely damaged or reformatted. "

      https://www.cgsecurity.org/wiki/PhotoRec

      1. Nattrash

        Re: Photorec

        But that is the root problem right? Most use some kind of program that is/ should be trusted to do a proper job. But then again, does it? Are you sure? In the end, nobody knows (apart from the person doing the recovery and finding your nude selfies).

        As for me; # dd if=/dev/zero of=/dev/sdX works for me. After that a shiny new partition table and were good to go. Sure somebody will tell me I'm ignorant (and saw the picture of the new wallpaper in my living room), but hey, it's a start ☺

      2. Doctor Syntax Silver badge

        Re: Photorec

        Upvote for both. I've used them to recover files from ransomware. The encrypted files hadn't overwritten the original data which had just been deleted.

      3. Loyal Commenter Silver badge

        Re: Photorec

        I usually use recuva to retrieve data from something with a corrupted filesystem.

        A 'fast-format' only removes the file tables, so the data is still there. A far as I am aware, this works just as well on SSDs / flash memory as it does on spinning rust.

        A full format (writing the same value to every byte on the device) is relatively slow, and should in theory remove all traces of data on SSDs / flash drives. However, it doesn't work quite as well with hard disks. Because physically overwriting the data on a physical disk doesn't write in exactly the same physical position, you can get 'margins' along the side of the tracks where the old values are retained, or echoes, where for instance if the new value for a bit is '1', it may actually be '1.01' if the previous value was also a '1' - the disk controller will read this as a 1, but other techniques may read it as '1, previously 1', etc. Whilst it takes expensive forensic equipment to recover data from these, I believe such a thing is practically possible.

        Proper erasure therefore involves overwriting the previous data multiple times, with random bytes, and if you want to be 100% sure, then permanently overwriting it with drill and bucket of bleach.

        1. TheMadMuskateer

          Re: Photorec

          Not sure how true it is that you can still get old data from the edges of the track or print through to deeper in the oxide layers - modern hard drives need enormous amounts of processing and error correction just to get back the data you *last* wrote.

          1. Yorick

            Re: Photorec

            That exactly. "Edges of the track" is 80s tech. I really don't see that this is a thing any more. Do nation states have tools, ludicrously expensive and big, maybe some kind of magnetic scanner for hard drives, that could do this on modern drives? Your guess is as good as mine. But if your adversary is a nation state, you got bigger issues than drive erasure.

            If you can get data back from a modern HDD, or Flash, or SSD, with PhotoRec or a similar software tool, or indeed any kind of hardware tool, after a single pass full format (procedure: Either dd the entire drive with /dev/null, or blow the part table away, create a new partition spanning the entire drive and choose to full format it during creation); and you've done me the courtesy of doing so in a way that a reasonable person would consider "verified, totally, dude", I will donate 50 bucks to the charity of your choice and consider myself put in my place / educated.

            I realize that "any kind of hardware tool" makes it more likely I'll donate something somewhere. That'd be worth it to learn about the kind of tools that can do this magic, and what their cost to acquire / use is.

            1. Loyal Commenter Silver badge

              Re: Photorec

              I believe the 'hardware tools' in question do involve disassembly of the drive in a clean room, and application of something more advanced than your standard drvie head, or at the very least, replacement of the disk controller to distinguish between that 1.0 and 1.01. I don't think it's nation state level stuff, more specialist forensic crime lab type stuff. You're probably still talking tens or hundreds of thousands of pounds, but I believe the capability exists.

            2. teknopaul Bronze badge

              Re: Photorec

              Some work has been done recently into hacking sd card firmware. This is done by legitimate retailers to indicate a drive manufactured as 32gb sd with lots of bad blocks is only 16 gb in size. Miscrecreants can increase the size. I suspect with similar software tools you could get access to data on bad blocks that would never be presented to the OS for deletion or wiping running standard firmware.

        2. Anonymous Coward
          Anonymous Coward

          Re: Photorec

          I don't remember where I saw it. But I think the US DOD rules for securely removing all data from a hard drive involved dissembling the drive. Grinding off all the magnetic material from the platters. Then burning the magnetic dust.

          And of course you have to do that quickly while the bad guys are boarding your ship/plane/Humvee.

        3. teknopaul Bronze badge

          Re: Photorec

          I suspect writing from /dev/zero to an SD will not work 100%. I think this will write zeros to all the good blocks but skip the known bad blocks. You might have to hack the controller to get access to the bad blocks and odd bits will be missing but I think is normal for SD to have a large percentage of bad blocks so quite a lot of data might be available.

          Better to physicaly destroy SDs if the have ever contained sensitive data.

      4. ibmalone Silver badge

        Re: Photorec

        IIUC, yorick's objection is that 'low level format' is about stuff like cylinders and not really something other than hard drive manufacturers do any more. A full format with erase is what you want, rather than simply replacing the filesystem superblock and leaving the tasty data in place for tools like photorec to rediscover.

      5. Reg Reader 1

        Re: Photorec

        Thanks for the mention of testdisk. I found that in the Debian repository and will have a lok at the tools and there are lots, as it turns out.

        As a longtime Linux desktop user who has decided to learn more about its administration, I've started with "Linux Bible" so I'm running Fedora in VirtualBox on MX Linux, my main distro.

        Hey, maybe it is THE YEAR OF THE LINUX DESKTOP! :)

      6. Jamie Jones Silver badge

        Re: Photorec

        A "format" just rebulds the neccessary index and structure of an empty partition - it doesn't physically wipe the data.

        "Yorick" was talking about low-level-formats - overwriting every block - a completely different kettle of fish

    2. John Brown (no body) Silver badge

      "A “low level format” is not so easily achieved with OS tools, though there are utilities for it. All it does for someone over a “full format” is map out bad sectors - that doesn’t make it more secure."

      And that's not exactly a new situation either. Back when I first got an HDD, a 20MB Seagate, only a low level format accessed by using DEBUG G=C800:09 (or something like that) would write to the entire hard disk. FORMAT C: even back then only re-created the root directory and scanned for bad sectors. And yet people today still act surprised when told formatting doesn't wipe the date. I've not tried with an SSD but would not be surprised in the least to find an OS level FORMAT does not write to the entire drive.

      1. ibmalone Silver badge

        Might not, but there are reasons other than security to want it to, I'd think formatting flash should probably perform trim for the allocated area to allow wear-levelling to continue to work properly. (Whether that zeros the data on the device or simply causes the controller to report zero on an attempt to read that area I'll admit to not knowing off-hand. But modern SSD should have a secure erase hardware feature.)

    3. Kevin McMurtrie Silver badge

      All drives have some spare capacity to cover for wear leveling and fault tolerance. Really good hackers can swap the firmware to access whatever is left sitting in there. It seems that such hackers would be extremely rare but, on the other hand, excellent hackers and researchers might be the only ones who actually buy very old storage devices.

  9. adam payne Silver badge

    Second hand USB sticks?!?! I didn't even know that was a thing. I figured everybody just destroyed them like I do.

    Why would you sell a USB stick let alone buy one second hand?!?!?

    1. My-Handle

      Yep, destroying them is definitely the way forward. I manage to destroy most of mine before I'm even finished using them :)

    2. Earache

      Believe it or not there are many people out there with no or very little disposable income who will go to great lengths to sell any junk that finds its way into their hands. And others who can't afford to buy new non essentials.

    3. Mullah Bob

      Huh! What ...wait a minute

      Wow...you mean you can reuse these things? I thought once they were full you threw them away.

      1. David 132 Silver badge
        Trollface

        Re: Huh! What ...wait a minute

        I thought once they were full you threw them away.

        Top Tip: if you put a piece of sellotape over the write-protect notch, you can re-write to the drive or delete stuff.

      2. DiViDeD Silver badge

        Re: Huh! What ...wait a minute

        " I thought once they were full you threw them away."

        My partner gave her father a digital camera as a present back in the day. A couple of years later, he mentioned that it was great how you could get so many pictures on each 'film', but that the film was terribly expensive.

        On investigation we found he had around 100 CF cards in a storage case. He'd copied all the pictures to his PC, but wanted to keep the 'negatives' safe!

        He'd even given away CF cards to neighbours so they could print their own photos from them!

        EDIT: I know how to spell 'neighbour'. Will someone please explain to El Reg's comment box how to spell it?

    4. Mark 85 Silver badge

      Destroying is the only way to go. As added plus, there's a lot of stress relief in placing USB stick on a hard surface and whacking it with large mallet. For added benefit, place a photo of your ex-boss/wife/whatever on top of it.

  10. SimonC

    Who even destroys them? I'm pretty sure in my Box Of Things I Will Definitely Need One Day I have usb sticks that are measured in tens of mbytes...

    1. katrinab Silver badge

      I guess I need to get rid of my old IDE drives, now that I don't own any computers that have the appropriate sockets, and also my collection of adapters that would enable me to read them on more modern computers.

      1. DiViDeD Silver badge

        @ katrinab Re:get rid of my old IDE drives

        Don't do that!! Fleabay has USB adapters for every kind of obsolete drive in existence - even 350 PATA!

      2. NorthIowan

        Old hard drives

        >I guess I need to get rid of my old IDE drives, now that I don't own any computers that have the appropriate sockets,

        Silly me. Was helping a lady from Church dispose of her old PC's after her husband passed away. Used Darik's Boot N Nuke on most of them. But his oldest PC could only read 5.25" floppies and I didn't have one with me and I'm not sure I could have made one at home even then.

        But not wanting to throw out a 20 Meg 5" hard drive (I never had a 5" hard drive) I took it out before taking the PCs to be recycled. Only later when I thought about wiping the hard drive did I realize that I needed the controller card as it was a preIDE drive.

    2. Loyal Commenter Silver badge

      I still have, somewhere, a present that was bought for me some years ago, consisting of a digital watch with a hidden USB cable underneath that gave access to... a 'secret' 32Mb flash drive!

      Spy tech of the future it was not.

  11. Alex Read

    Not just ebay... I volenteer at a charity shop where I try to salvage IT kit - test it, wipe it & pop it in the shop for reselling.

    Never really been sure which is the best sort of military grade etc. disk wiping tool I could use - any suggestions please (ideally open source/free)?

    1. Adrian 4 Silver badge

      @alex read

      dban

    2. HWwiz

      @Alex Read

      I work in a banking DC and we use "Blancco", as do most DataCenters. And then after Blancco has finished and generated a Certificate of wipe, we then put them in the crushing machine.

      Ive worked for 2 different banks, and they both use this same process.

    3. Jamesit

      For using drives in the shop I use MHDD, on drives for resale I use DBAN. I used TestDisk to try and recover data after MHDD and nothing could be recovered YMMV.

      The RCMP recommends DBAN for sensitive data.

      http://hddguru.com/software/2005.10.02-MHDD/

      https://dban.org/

      1. Jamesit

        DBAN download link http://sourceforge.net/projects/dban/files/dban/dban-2.0.0/

        DBAN.org doesn't load for me.

    4. doublelayer Silver badge

      A good erasure tool: dd. For a typical disk, if=/dev/zero. For a disk that you a) want to sell and b) want to be very sure about*, do a zero pass, a random pass, a 1 pass, another random pass, and a final zero pass. Have fun getting through that.

      *In reality, a disk that is old enough such that data can be realistically recovered after zero passing it without government-level hardware is probably not worth reselling. A disk that contains data so critical that you are worried that it might still be recovered after the multiple passes I suggested should be physically destroyed.

  12. Dave Hilling

    UGH

    You would think by now with technology what it is, that when you empty the trash on a windows machine it would mark the file to be deleted and it would go back as a background process and write random data to at least make a good faith effort that it cant be recovered, it should be the default setting and maybe allow you to change it to x amount of days or something. I use 3rd party stuff to do it now, but it should be included.

    1. Adrian 4 Silver badge

      Re: UGH

      Yeah.

      But then people wouldn't be able to undelete - and I suspect that would be a much worse security / convenience / frequency tradeoff.

  13. DCFusor Silver badge

    Ah, it was easier before they all had on board cpus

    Then users of the penguin could just dd to the drive from /dev/zero.

    Then along came behind-your-back wear leveling and sector remapping, reserves held back to replace failing sectors and so forth.

    And oldie but goodie, I think one can assume it's only become more interesting since, with big SSDs as well. Bunnie and Xobs on what's really in flash devices:

    https://www.bunniestudios.com/blog/?p=3554

    And now there are even rubber duckies, although at the price, I doubt people are selling them cheap or leaving them around much other than for targeted pen testing.

    https://shop.hak5.org/products/usb-rubber-ducky-deluxe

    I've been downvoted here before for pointing out that the flaw in USB that has it "believe" a device is what it says it is cannot be fixed and keep back compatibility. I'm still correct about that.

    A regular format, despite a wrong statement above, never did much more than erase the "allocated" bits in the filesystem. Maybe if you formatted to a completely different filesystem or did a complete write-read error check, but I've seen some tests that then put the original data back, sector by sector.

    1. doublelayer Silver badge

      Re: Ah, it was easier before they all had on board cpus

      "I've been downvoted here before for pointing out that the flaw in USB that has it "believe" a device is what it says it is cannot be fixed and keep back compatibility. I'm still correct about that."

      I didn't see this before and am not downvoting, but that point is somewhere between off the path and wrong. USB devices are what they say they are. A malicious device issuing keyboard commands is a keyboard. It needs to be identified as a keyboard in order to do keyboard things. It might be a physical keyboard with keys, a programmable keyboard, a dongle for a wireless keyboard, or a thing that issues key commands for a malicious purpose. In all cases, it is a keyboard. The computer does not err in trusting it when it says it is a keyboard. It errs when it doesn't ask for verification that the user intends to connect a keyboard. Of course, such verification can be difficult if that is the only input device available, so that is a thing to consider when trying to install a more restrictive policy. However, the "flaw" you have identified is a feature of USB that is required for the thing to be universal. The only way to change that is to have separate incompatible ports for each type of device (I'll vote against that).

  14. A. Lewis

    Filed under "news that surprised no-one"

    And the biggest source is surely second hand computers and tablets, rather than actual USB sticks.

  15. Version 1.0 Silver badge
    Meh

    I think we can blame the operating systems

    The operating systems all say that they are going to "reformat the disk" and so the average user is going to think that they have done the right thing. It's way past time for the operating systems to offer an "erase disk" option that actually does what it says it does instead of just clearing the file table.

    1. 1752

      Re: I think we can blame the operating systems

      Not that I know IOS that well, but that has a 'erase disk' option from memory on the format part of the disk thingy.

  16. HWwiz

    Used USB sticks

    Aside from the actual story. Who on earth buys 2nd hand usb sticks ?. For gods sake they only cost a few quid new.

  17. Zarno
    Coat

    DBAN.

    Mine's the one with the bright red USB pen and neon orange mini-CD both set to "nuke first, ask questions later" automatically without intervention if left in a PC.

    EDIT: Drat, seems it was bought and now shills out for some crummy "pro grade" solution...

    Looks like I need to keep my original media safer...

    1. jelabarre59 Silver badge

      EDIT: Drat, seems it was bought and now shills out for some crummy "pro grade" solution...

      Looks like I need to keep my original media safer...

      Just boot with a Linux liveCD and run the "shred" command against the drive device (/dev/sdX). You can have it run enough passes to duplicate a DoD wipe, works just as well as DBAN.

      1. Zarno
        Mushroom

        it's a convenience factor thing mainly, since a few tweaks on the DBAN ISO allow "Press key to cancel winter." vs "Shall we play a game?".

  18. Stuart Dole

    Wondering how many USB sticks come from estate sales - the people who handle this sort of thing probably don't care too much about erasing things. Though they probably shred paper records?

    1. katrinab Silver badge

      Bankruptcy sales are a big source of this sort of thing.

  19. gz3zbz

    Tip for Windows users

    Windows has the cipher command which can be used to overwrite free space on a drive, e.g. cipher /w:F:\ will overwrite free space on F: with 0x00, then 0xFF, then random numbers.

  20. Jamie Jones Silver badge
    Happy

    Pretty bad erasure rates in these samples....

    .... did they buy them all from ex-government auctions?

    1. DiViDeD Silver badge

      Re: Pretty bad erasure rates in these samples....

      "did they buy them all from ex-government auctions?"

      I'm sorry, but the government does not have any used USB sticks available for sale at present. Because your government cares about your security, it will continue to practice its standard secure disposal policy, and leave them on trains.

  21. jelabarre59 Silver badge

    Like my cars

    I use my USB sticks like I use my cars. I run them until they're no longer usable/repairable. By then they're well and truly dead.

    Of course, the absolutely-dead USB sticks I usually take a hammer to afterwards. The car usually requires a "blue-tip wrench".

  22. Aynon Yuser

    What a nice way to troll. Leave pics of ones anus on a computer.

  23. hayzoos

    Multiple pass overwrite is a waste

    Best: Proper physical destruction, choose your favourite method, just be thorough.

    next: Any secure erase function built-in, fastest possible overwrite, may overwrite bad "blocks", use hdparm to access it

    next: single pass overwrite ones or zeroes or preferably random bits, use dd with random or zero, slower than built-in due to interface bottlenecks

    next: overwrite software like dban, blancco, or whatever with one or more passes to meet regulatory requirements including certificate, slow as molasses at the north pole

    Format was never meant to erase, only prep for use. The same goes for "Low-level" or "Full" or "Guaranteed complete thorough better than new" format which may or may not overwrite all accessible blocks, it usually is used when there is no existing format or changing to a different format.

    Windows cipher command is a good try, but it fails on multiple levels.

    Delete, trash, recycle, hide, forget, ignore, store in vegetable drawer, will also not properly dispose of sensitive digital bit patterns.

    I like to disassemble and apply a propane or mapp gas torch to the bit holding parts. For the really sensitive stuff I would use a microscanning microplasma torch or microsharks with microlasers.

  24. herman Silver badge
    Devil

    Microwave oven

    To erase the SD cards/USB sticks, microwave them for a few seconds, then sell them on Ebay...

POST COMMENT House rules

Not a member of The Register? Create a new account here.

  • Enter your comment

  • Add an icon

Anonymous cowards cannot choose their icon

Biting the hand that feeds IT © 1998–2019