The Mystery of the Constantly Changing MAC Address

[cruikshank]

A while back I bought a refurbished HiSense Sero 7 Pro Android tablet to use when I don't want to carry around my 10 inch tablet. Except for having some trouble updating, it has been a great device. So when my wife's cheapo tablet broke recently I got her another refurbished Sero 7 Pro. Every day when she turns it on I get a message that there's a new device on the network and it shows another MAC address for her device. Since the network thinks it's a new device DHCP also leases out a different IP number each day.

My MAC address is stable on my Sero. Anyone have an idea what might be going on?

[Slacker]

A MAC is a hardware address of the device it can't change on it's own, so if you constantly see a new address, there is always the possibilty of a hacked device and someone trying to get on your network, or the hardware is bad and doing something odd, but even then the address should not change, from what I understand this is impossible to do so.

With the old tablet and new one, being the same types of devices there could be some odd MAC thing going on possibly with your network, conflicted with the old and new devices.

I'm assuming we're talking about seeing this MAC on a router? If so you could just do a router reset and clear it all out and see how that goes, might just be some Firmware glitch in the router.

Or your network could be compromised so make sure it's secure, and if after clearing the router and you still have the issue, reflash the router and see if that helps and if not get rid of that device, it could have a backdoor in it.

[cruikshank]

Slacker, thank you for your reply. I realize the MAC address shouldn't change. They can be hacked, but there's definitely something weird going on. I believe my network is fairly secure. The only time I get messages about a new device on the network is when she turns her tablet on. I don't believe it's the router either, as I have used this router with the same DD-WRT firmware for years and there's no problems with any of the other wired and wireless devices connected to it.

I was letting my next door neighbor connect to my network for almost three years before I cut her off a few months ago. In that time some of my account information was compromised at two different times. I finally had enough as you're only as secure as the weakest link on your network. I have had no problems since. When I used to help her with her laptop it was running non-genuine Windows and was full of malware. She used to ask for help for the most simple problems though so I really doubt she would know how to hack my network. Her latest boyfriend doesn't seem like much of a genius either.

I'm going to try putting her tablet on the 5ghz network to see if that helps. This is really weird what's been going on. When I do a manufacturer lookup on the MAC addresses I'm getting it just shows "Not Found".

[Slacker]

Seems like a bad tablet...

Best to connect other devices to the router and see if it still continues to happen, try to connect some wifi cellphones, computers and other tablets to test it out...

Hey remember, they're going to hack you playing like they're the dummy, 'Social Engineering' LOL... Watch out for the ones that play the fool...

But I'm sure this was not the case this time...

[cruikshank]

Hey, Slacker. You're probably right, it's gotta be something in the tablet. I have three other tablets on the network including one of the same make and model, no probs with that one or any of them. Then there's a PS3, two iPod touch, a laptop, a media drive, a printer, and two streaming TV boxes. Never had a problem with any of them. It's a really strange thing. Other than that the offending tablet works great. I have Lookout security on all the Android devices.

[Slacker]

Try another tablet and let us know...