Bizarre Thumb Drive partitioning and formats

[oshunluvr]

Several years ago I saw an ad on Amazon for a set of 3 USB 2.0 16GB memory sticks for $5. I suspected that they were phony but ... When I looked at them with gparted they listed as 16GB. They had a partition setup that was as weird as what you noticed. But, I used a verification program that writes then reads 16Kb at a time till the stick doesn't read back what it just wrote. The three sticks were actually 256Mb

When I see stuff like that my first thought is that hidden in all that garbage is malware.

Yeah me too. Had a similar phoney-size experience with a MicroSD card. Seems we "suspended" the "...no free lunch..." adage, right? I thought about that in this case, but what's the point since the car dealership isn't selling thumb drives - no reason to obfuscate the actual size of the drive.

Malware is possible, but if so it isn't very well hidden - at least not from someone with my amazing skill set, LOL. I did decide right away that I'm not plugging it into a Windows install. Maybe I will to a VM just for fun and see what happens.

[GreyGeek]

Several years ago I saw an ad on Amazon for a set of 3 USB 2.0 16GB memory sticks for $5. I suspected that they were phony but ... When I looked at them with gparted they listed as 16GB. They had a partition setup that was as weird as what you noticed. But, I used a verification program that writes then reads 16Kb at a time till the stick doesn't read back what it just wrote. The three sticks were actually 256Mb

When I see stuff like that my first thought is that hidden in all that garbage is malware.

[oshunluvr]

Yeah, that was the plan. I'd never seen such a wacky setup before so the post was just out of curiosity.

BTW, I see you have the same affliction I have - "Trailing Pinky Shift Syndrome". It where you capitalize the first TWO letters of a sentence instead of just the first! ROFL

and yes, I made that up.

[mr_raider]

SOme USB drives come from teh maker with some crappy program that auto installs in windows on first installation. They are configured to like an autorun cd-rom from the old days.

Just copy the files off to another device, and verify their integrity. Once that is done, destroy the partition table on the device.

[oshunluvr]

We bought a car a couple weeks ago and is the way these days, the dealership scans and keeps the signed paperwork and gives you a thumb drive with a the scanned docs on it. I plugged it in this morning to copy the docs to my server for storage, no problems.

The first odd thing I noticed is it showed up in Dolphin as a 123 MiB fat16 partition. The size struck me as odd. Then I noticed at mounted as SDI (whole device), not SDI1 (a partition)

Now I'm curious, so I dug in.

From dmesg:

[FONT=monospace][COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]usb 1-6.3[/COLOR][COLOR=#000000]: new high-speed USB device number 11 using xhci_hcd[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]usb 1-6.3[/COLOR][COLOR=#000000]: New USB device found, idVendor=1221, idProduct=3234, bcdDevice= 0.00[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]usb 1-6.3[/COLOR][COLOR=#000000]: New USB device strings: Mfr=1, Product=2, SerialNumber=3[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]usb 1-6.3[/COLOR][COLOR=#000000]: Product: Flash Disk[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]usb 1-6.3[/COLOR][COLOR=#000000]: Manufacturer: USB2.0[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]usb 1-6.3[/COLOR][COLOR=#000000]: SerialNumber: 2007062017300531[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]usb-storage 1-6.3:1.0[/COLOR][COLOR=#000000]: USB Mass Storage device detected[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:58 2020] [/COLOR][COLOR=#B26818]scsi host7[/COLOR][COLOR=#000000]: usb-storage 1-6.3:1.0[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]scsi 7:0:0:0[/COLOR][COLOR=#000000]: Direct-Access     USB2.0   Flash Disk       2.60 PQ: 0 ANSI: 2[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]sd 7:0:0:0[/COLOR][COLOR=#000000]: Attached scsi generic sg9 type 0[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]sd 7:0:0:0[/COLOR][COLOR=#000000]: [sdi] 251904 512-byte logical blocks: (129 MB/123 MiB)[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]sd 7:0:0:0[/COLOR][COLOR=#000000]: [sdi] Write Protect is off[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]sd 7:0:0:0[/COLOR][COLOR=#000000]: [sdi] Mode Sense: 0b 00 00 08[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]sd 7:0:0:0[/COLOR][COLOR=#B21818]: [sdi] No Caching mode page found[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]sd 7:0:0:0[/COLOR][COLOR=#B21818]: [sdi] Assuming drive cache: write through                                                                                                           [/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#000000] sdi:[/COLOR]
[COLOR=#18B218][Mon Jul 13 08:45:59 2020] [/COLOR][COLOR=#B26818]sd 7:0:0:0[/COLOR][COLOR=#000000]: [sdi] Attached SCSI removable disk[/COLOR]
[/FONT]

Opened the drive with Partition manager. and it gets really odd:

• 4 partitions, out of order, separated by 3 sections of unallocated space
• The 4 partitions show their mount points as /run
• The 4 partitions show as "Unformatted"

From Partition Manager, in disk order:

2018;538988360 Unallocated - 257.01 GiB
538988361;1077964648; sdi3 - 257.0 GiB
1077964649;1,394,614,303; Unallocated 150.99 GiB
1394614304;1394635640; sdi4 - 10.42 MiB
1394635641;1684955423; Unallocated - 138.44 GiB
1684955424;3386954047; sdi1 - 811.58 GiB
1998616933;2542722764; sdi2 - 259.45 GiB

The partition types are all "unknown" but fdisk shows them as:
1; 6c
2; 6e
3; 79
4; 53


The only thing I can think of is it's some sort of encryption scheme but it didn't need a password or anything to access the folder and files. I was able to rename the folder, create a new folder, and copy the files off of it.

Odd.

I suspect the sizes are phony and it's not a 2 TiB drive - LOL

I will eventually wipe it (if I can) an use it as a throw away, but I was curious if anyone had any insight into what was going on before I destroy it.