AT&T Microcell Disassembly; Security Flaws Exposed
CharlyFoxtrot writes "The geeks over on the fail0verflow blog took apart an AT&T Microcell device which is 'essentially a small cell-tower in a box, which shuttles your calls and data back to the AT&T mothership over your home broadband connection.' They soon uncovered some real security issues including a backdoor : 'We believe that this backdoor is NOT meant to be globally accessible. It is probably only intended to be used over the IPSEC tunnel which the picoChip SoC creates. [...] Unfortunately, they set up the wizard to bind on 0.0.0.0, so the backdoor is accessible over the WAN interface.'"
That's why I bought a Saturn.
AT&T's customers routinely take it in the backdoor from the company already so they just figured that no one would notice in this case.
The box is only ‘allowed’ to work when within the area nominally serviced by AT&T.
Very cool would be any trick to overcome this limitation and have local cell service wherever you may be.
I am literally 3000 tokens away from the chaotic crossbow --Stephen
If they're pricey, insecure, and can't be used outside of the normal AT&T range, what's the point, really? About the only usage I can think of would be providing interior building cell phone service in massive structures, such as conference hotels, where the signal from outside is too weak to penetrate twenty layers of concrete.
Occasionally living proof of the Ballmer peak.
How to spoof GPS indoors?
Let it pick up a signal for an arbitrary location.
I killed da wabbit -Elmer Fudd
Brought to you by the same guys charged with domestic evesdropping: http://www.wired.com/science/discoveries/news/2006/01/70126
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The most interesting thing I thought was that the device uses an IP multicast address for the backdoor reply. This makes it possible to search for all Microcell devices across the network, as long as its not behind a router that blocks IP multicast.
Actually, you're incorrect in your thinking. They were required to put GPS in it for E911 to work and the device will not function until the GPS location is verified. As the owner of a microcell I can tell you that GPS reception is the biggest #$@!@# pain in the ass for the thing in general. I have a metal roof at home and the microcell will only activate for me if I hang the device in the skylight.
Actually, the GPS is most likely there to provide a precise time reference...required by GSM.
What a hassle. Instead just get a signal booster from Wilson Electronics and bring the cell tower signal into your home. Perhaps something like this: http://www.wilsonelectronics.com/ProductDetails.aspx?Product=19&title=AG+SOHO+60+(801245)&Category=9
Joshua
Sorry, could resist for all the peeps, who like me, first heard of backdoors in Wargames. I was just a young peep who discovered the world of computers and was hooked, then saw wargames and thought, hmm, there's some shit i didn't think of.
Be seeing you...
I'm a Rogers customer out of Ontario with a wifi-capable cell phone. Reception in my neck of the woods sucks. However, my phone (a Blackberry Curve) has built-in wifi and supports UMA. For $5 / month extra, I can piggyback my calls over broadband internet and they simply get billed against my minutes. I can use this with any wifi hotspot in Ontario (and probably in Canada).
Pros: no hassles with GPS, placing equipment near windows; portability (don't have to take a microcell with me); cost
Cons: used to be a free service, but is not anymore; a UMA-compatible handset is required to leverage this
Have EVDO, will travel.
Having done a bunch of reversing work on similar and other platforms, most of this can be taken by extracting the interesting binaries from the firmware images then running them on an emulated image of the OS.
There is a backdoor to almost every system I have tested. You can bet that if it has an OS, it has a backdoor from either the chip fab, the OEM, the software developer or the vendor, often more than one they aren't aware of. It's not a conspiracy, it's just human nature.
All voice communication should be handled over a data connect and handed off to WiFi when available...
Anyone notice that if you are home all day, and your phone is associated exclusively to the Microcell, your phone battery is dead before the end of the day. Whereas if I am away from home the whole day, my battery will last all the way to the next day (almost twice as long) I've come to the conclusion that the Microcell kills the battery while paying attention to actual phone use, for example only 1hr of actual talk time, data usage only for syncing email via Exchange. In all my tests bluetooth is always off, wifi is always off. As an owner of this Microcell, which I also install for many other people, I can confirm a GPS lock is required when power is applied, but after that you can move it away from the window. Getting a new IP from your ISP will not always trigger re-sync of the GPS, often times it will re-establish the IPsec tunnel with the GPS light ever going into blinky-blink mode (searching)