this post was submitted on 10 Aug 2025
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Got a used business laptop and found a recessed dongle in it. The original owner says they have no clue, that it’s been in there since they got it. There’s no way a dongle is keeping this thing running, is there? I’ve already swapped the OS, if that matters at all

Update: yubikey! Thank you all for the information, I’m definitely still learning

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[–] l_b_i@pawb.social 48 points 3 months ago (1 children)

Looks like a yubikey. You should be able to list usb devices and it would show up.

[–] Semi_Hemi_Demigod@lemmy.world 14 points 3 months ago (2 children)

If it does it will show up as a keyboard

[–] wildbus8979@sh.itjust.works 9 points 3 months ago

That's only true if the password option is enabled.

[–] l_b_i@pawb.social 3 points 3 months ago

it might enumerate as a HID type device, but it will identify as a yubikey.

[–] litchralee@sh.itjust.works 45 points 3 months ago* (last edited 3 months ago) (1 children)

It looks a lot like a Yubikey, which is used to securely authenticate to company resources like a VPN. Fortunately, unlike losing a hard drive, a Yubikey can be deauthorized by the company and thus the device becomes useless for malicious use.

So if you want to use that USB port for something else, it shouldn't be a problem to remove a Yubikey for the prior user's employer.

[–] owenfromcanada@lemmy.ca 19 points 3 months ago (1 children)

Can confirm, I have one just like this. The giveaway is the conductive metal bit, to have it be able to detect finger taps.

You should be safe to remove it. It probably has some info stamped on the metal somewhere.

[–] litchralee@sh.itjust.works 12 points 3 months ago (2 children)

I've never had a need to use a Yubikey, but is that the button which spews gibberish into DMs? I've seen that a lot at work on Teams lol

[–] BuccaneerScientist@discuss.tchncs.de 7 points 3 months ago (1 children)

Sound about right. A YubiKey will print a one-time password when touched, by default.

[–] hoppolito@mander.xyz 4 points 3 months ago (1 children)

Do you know if this functionality can be turned off? I've been stung by the 'gibberish' once or twice but never enough to dive into the docs for it :)

[–] zaphod@sopuli.xyz 3 points 3 months ago* (last edited 3 months ago)

Yes, you can configure what happens when you touch the button.

[–] owenfromcanada@lemmy.ca 5 points 3 months ago

Yes, that's exactly what it is. I had to get one for work because they wanted everyone to use the MS authenticator app on their (personal) phones. I got the Yubikey instead.

But yeah, gotta watch that you don't accidentally touch it. I had a colleague carry my laptop once and was surprised to find some interesting additions to my code.

[–] laranis@lemmy.zip 18 points 3 months ago

I think this is a solved question based on other comments, but can we take a moment to admire that OP has the self control to ask BEFORE removing the device?

I am much more of a push-the-big-red-button-to-see-what-happens kinda person. That dongle wouldn't have lasted a second on my bench.

[–] winxp5421@lemmy.world 15 points 3 months ago

Possibly a hardware security key like a yubikey

[–] seathru@lemmy.sdf.org 11 points 3 months ago* (last edited 3 months ago) (1 children)

What operating system did you put on it? Should be able to find it in your devices list. Or at least a device id to work backwards from.

[–] Gullible@sh.itjust.works 8 points 3 months ago (2 children)

Just swapped to mint (mate) so it’ll take me a minute to find out how to do that. Will update when I find out. Posted this as I headed out the door, not expecting answers to pop up anywhere near this quickly on a community with a post per month. I am endlessly surprised and delighted by lemmy

[–] azdle@news.idlestate.org 7 points 3 months ago (1 children)

The command you're looking for is lsusb. There's going to be a lot in there, but for a security token like that, you're probably looking for something that says "yibikey", "Fido", or "u2f".

[–] Gullible@sh.itjust.works 4 points 3 months ago (1 children)

Thank you! I do have a question though. What does the “ls” in lsusb stand for? I’ve found several query commands that begin with ls and it might help me remember them a bit better if I understand what they mean

[–] seathru@lemmy.sdf.org 8 points 3 months ago* (last edited 3 months ago) (4 children)

I don't know it's proper name but "list" is an easy way to remember it. Want to see a list of what's in a folder? ls. Want to see a list of USB devices? lsusb.

[–] Zachariah@lemmy.world 10 points 3 months ago

The name inherited from Multics and is short for "list".

https://wikipedia.org/wiki/Ls

[–] Gullible@sh.itjust.works 4 points 3 months ago

Alright, that’s not hard to remember. Thank you!

[–] SatyrSack@lemmy.sdf.org 3 points 3 months ago

ls or l is also often used as an option/switch that is passed to another program to list something. Want to list all active Screen sessions? screen -ls. Want to list all mounted filesystems? mount -l

[–] vaionko@sopuli.xyz 3 points 3 months ago

List of PCI devices? lspci.

[–] seathru@lemmy.sdf.org 6 points 3 months ago* (last edited 3 months ago) (1 children)

Oh yeah, you should find lots of tutorials on identifying unknown devices in mint. It probably is a yubikey like others have said; but it would be a good way to teach yourself a useful linux skill if you want to learn it.

[–] Gullible@sh.itjust.works 4 points 3 months ago

Found it! It was listed incredibly verbosely, fully spelling out yubikey and then their website. Thank you!

[–] Bonesince1997@lemmy.world -1 points 3 months ago (1 children)

I can't believe they use SS and a lightning bolt 😂

[–] Gullible@sh.itjust.works 7 points 3 months ago

It is a bit silly, but it’s always been the usb3 symbol