Fake USB capacity?

I’m sure I am not alone when it comes to purchasing an USB stick that purports to be of a greater capacity than it truly is.

The way to test this is to use this command:’’’ f3probe --destructive --time-ops /dev/sd??’’’

This will reveal the true capacity. Be aware this will wipe the USB stick.

Then just format a partition on this drive to the real capacity and use that, so you can still use the drive, albeit much smaller than purported to be.

The other point I’d like to make is all os’s will still report the capacity as the fake one. This is because the fraudster used an industrial tool to hard-code in the USB flash controller’s firmware an inflated size. Those tools are mostly Microsoft only and proprietary to each manufacturer and USB stick series.

The upshot is you will still be able to utilise the drive as it’s true size, but not for using as a bootable install disk, as the disk will be written as the fake size. It can still be used for data only.

3 Likes

Not a support request, moved to the Lounge

Thanks for sharing.

Can you please share the names of the Manufacturers that you have encountered this issue with? That would be a greater service to the Community.

If not, could you point to a site that does report such a list of questionable USB sticks?

@ericmarceau and @rubi1200 Thank you for slotting this into a more appropriate area - I wasn’t sure where to post it.

I bought several of these on the off-chance a couple may be genuine, knowing full well the chances were pretty slim! Several from ebay, also a few from aliexpress and also from gogroupie. They all are noname brands-what a surprise!

If the high-capacity USB stick looks too cheap to be true - it most likely is.

I haven’t come across any site which has any sort of list so far, sorry. This is from Chatgpt:

Controller vendor Tool name examples
Phison Phison MPALL, MPTool
Alcor Micro AlcorMP
Silicon Motion (SMI) SMI MPTool
Innostor Innostor MPTool
USBest UT163 MPTool
Skymedi SK6211 MPTool

Manufacturer repair tools

Sometimes distributed internally or leaked:

  • Often Chinese-only

  • Poor documentation

  • Very fragile UI

  • Frequently flagged by antivirus (false positives due to low-level access)

These are the same MPTools listed above, just bundled differently.

Each tool:

  • Works only with specific controller models

  • Often requires:

    • Correct version

    • Matching VID/PID

    • Correct NAND parameters

Using the wrong one can brick the device

Here is a youtube (American) that shows how good some of the fakes look: Youtube

3 Likes

I have had an experience with this. The fake capacity had been raised by a huge amount; I forget how much, but it was something like 100 times!

There is a third-party app that will check this, and it provides both destructive and non-destructive tests.

The name is Fight Flash Fraud.

Commands include f3write, f3read and f3probe (the latter is fast). There’s also f3fix, which is supposed to correct the reading on the USB stick, but I haven’t tried it.

Here’s a video showing you a brief rundown of f3probe and f3fix.

3 Likes

Hello,do you think using Rufus to create a bootable drive with this USB would increase the success rate?

@paddylandau Yes I only included the f3 size checking command in my first post, thanks for elaborating. F3fix doesn’t do much for me…

There is also a QT version if you don’t like the cli, but it is pretty slow.

1 Like

@qwedsaz No. The reason for this is the fake size is hard-coded into the drive’s firmware, so the o/s (whatever it is windows or linux) system reads this firmware to designate what the drive is. Rufus or any other usb writing software takes whatever o/s the system says the capacity is and treats it as such. Having said that if you have a really small o/s such as Puppy linux that will only take a couple of gigabytes, you may have success with that as it will write to the first sectors of the drive and will not stray into the fake area. Try it and let us know!

2 Likes

Are there any particular sizes that are more likely to be “mis-represented” than others?

Or are all sizes from each of those manufacturers suspect?

@ericmarceau 2Tb followed by 1Tb seem to be the favourite sizes.

They are usually a real size of about 32gb.

I had a couple of Sony USB sticks that purported to be 2Tb but were 32Gb sticks.

These were very low priced, but I thought I’d take a punt, they were priced at what I would expect to pay for a 32gb stick, so I wasn’t really surprised/bothered when I found them to be fake.

All the other sticks I bought that were faked sizes were unknown brands.

Cheers Tony

1 Like

When it happened to me, it was a fascinating learning experience!

So many crooks on this planet.

3 Likes

@Vidtek99 Thank you for the thorough and clear explanation! The point about firmware-hardcoded fake capacity is particularly insightful. I don’t have a suitable drive to test the Puppy Linux idea right now, but I’ll keep this in mind if I encounter a similar issue in the future. Really appreciate your help!

2 Likes

So … if they can mis-represent the size of USB sticks, would they do so for SSDs?

1 Like

They will probably do it for ssd’s and M2 drives once they get their hands on the firmware writer software. As @paddylandau says crooks will be crooks…

2 Likes

This topic was automatically closed after 30 days. New replies are no longer allowed.