Is it safe to buy a second hand 4g dongle online in terms of it having some malware or such?
 

I read about rare cases for usbs.

Crypto guys are super paranoid about buying hardware and say you must always buy new.

Is it an issue?

4g dongles seem pretty rare here in the UK and the new ones cost 40 GBP and up but 2nd hand only a few quid.

I could afford to buy new if absolutely advised but is it unnecesary from a security standpoint?

I would read up on the available information about the device you are interested in. IF it presents as an interface device or I/O channel and contains no writable storage it is probably safe enough. Not that it could not be leveraged to be a threat, but why would someone work like crazy to make one a threat when other devices make it SO EASY?

Do you have a LUG in your area? You might contact them and see if the group seems trustworthy and does a hardware swap night once in a while. They might be good people to talk to about other hardware and OS issues and questions as well.

I cannot suggest one, because only your vocabulary suggests you might be in the UK. Neither your profile nor your question provide any information that might refine the answers. (DO NOT put information about your address, but something about your country or timezone might not be risky.)

From a security stand-point, one should never buy a second hand USB drive (unless it's your buddy selling it) as it be to much of a risk. That's my opinion. YMMV. Also you don't know how 'well used' the drive is. Could be on last legs for all one knows... Why would someone be selling it? I mean, I use mine until either they have problems and then wipe it/break it and into the bit bucket it goes.

Maybe it's just my nasty suspicious mind, but, unless I was able to thoroughly vet the seller, I'd be concerned about the health and potential longevity of the item.

I've read in legitimate sources about persons reselling used laptop batteries as if they were new on various on-line merchandising sites.

linuxuser371038,

Here is one on Amazon UK:
https://www.amazon.co.uk/TP-Link-M70...ct_top?ie=UTF8

Buy new and sleep easy at night!

Having looked in to mobile connectivity recently there appear to be three main types of USB device:

USB 4G "dongle" These generally appear first as a mass storage device (to make it easy for Windows users to install drivers) and then switch to modem mode when the driver kicks in. You'll need to check that specific drivers are available for your linux distribution as otherwise it can be a bit of a headache.

USB 4G "Sharing" like the one beachboy2 mentions above, these come in a couple of sub-flavors, I've one that's USB and the other that's self powered. The self powered ones show up as a hotspot that you connect to, and then they provide the outbound connectivity. These are easy to set up as there's no drivers needed. The USB ones enumerate as another ethernet device on the host and through DHCP connect directly to the "router" part of the hotspot as though it was a wired connection.

"Dumb" USB modem These show up as a /dev/ttyUSBX device and are really much more for things like dial-up / SMS rather than giving full time 4G "mobile data" connectivity.

For anything other than the "Dumb" USB I'd be wary of buying used as the "router" part of the firmware could be modified and doing strange / naughty things.

Where is the insert quotes button I couldn't find it anywhere?

Anyway seems there are a few people here as paranoid as me! Makes me feel better about shelling out the extra cash for new now :).

linuxuser371038,

Try using this for quote tags:

[quote=John Doe;5685032]

Lorem ipsum dolor sit amet

Then put /quote in square brackets [...] immediately after amet.

This will give the following output:

Might be able to buy one that allows some firmware update. One can check that via shal or such and reload it.

Amazon has 10 packs of new 4G USB2 thumb drives for $20USD with free delivery.
How is it worth th risk to buy used?

Because they don't all have the same functionality.

It seems only the older discontinued ones expose the serial modems whereas new ones use the RNDIS ethernet connection like mobile hotspots. I want to use the former for AT commands. Plus RNDIS is some microsoft crap. Avoid whenever possible.

So guys, to follow up I have been doing quite some more research and it seems the second hand market is where most of these devices I want are available. Very very difficult to get my hands on a 4g GSM modem new now. Been trying all week. Bought one, thinking it was just what I wanted and there was a firmware update in the last few years rendering that funcntionality obsolete.

The newer ones use RNDIS making a wired connection which is different from the classic ones which make a device. Seems makers transitioned to this new style across the board of the few that are still available.

So, having said that, 2nd hand market is where I could most easily get one.

As such is there much risk of one having some malware tacked on it? I know I went most of my life not thinking about this stuff and did not have such issues buying 2nd hand quite often. I am very paranoid these days though.

It would not be hard to make a "USB appliance" out of a Raspberry Pi Zero (if you can get one) plus a 4G HAT. At its most basic, you'd just connect a USB cable to the Raspberry Pi's data microUSB port and send data and power over that, leaving the power microUSB port unconnected. There is also a HAT or two to provide USB.

For less current, you might be able to do something similar with an Arduino Every Nano plus 4G.

Then 3D print case, if you can use FreeCAD. Or just wrap it in beautiful electrical tape.

A nice out of the box idea but what is the point of doing that when it costs about 10x the price and also 10x the effort than buying one made for the job?

I just looked at a 4g hat and on pihut first result I see is £82. Add £30+ for a pi and probably other accessories to put everything together I fail to see any advantage in that then a load of setup installing OS and such for no benefit over a device which is a fraction of the cost.

I have seen there are some non brand name gsm modems floating around such as the OSTENT GSM modem someone has recommended in another thread reply. That seems similar in price to the classic 4g dongles.

Guys just how risky is buying 2nd hand I want clarification on that?

A gumtree seller I found sounds genuine and found an old model that should be the one I want.

Surely there is not much of an attack surface for an obscure old 4g usb dongle sale? As well wouldn't it be a case of them only targeting windows if it is the case?

I much prefer buying 2nd hand really not only for the economic aspect but also to bring old, otherwise unloved, hardware back to life.