On 13 Sep 2013, at 10:04, Eugen Leitl <eu...@leitl.org> wrote: > On Fri, Sep 13, 2013 at 06:39:35PM +1000, Erik de Castro Lopo wrote: > >> Yes, but Firefox OS and Cryanogenmod only control the user facing part >> of the smartphone. Loading eg Cryanogenmod onto a android phone leaves >> the software running the radio part of the phone untouched (otherwise >> the phone would never have passed the regulator auhorities). The second >> link I posted reported a vulnerability in that software. Secondly >> these phones connect to the cell phone network and you and I have no >> tools to examine what happens on that network. > > Baseband processors leave the system wide open to all kind of attacks. > Countermeasure would be running the 2G/3G/4G stack in an open > source SDR radio, or using an open source VoIP device that connects > by WLAN to a MiFi, which is considered part of the untrusted > Internet. > > The open source WLAN VoIP handset is more difficult than it appears. > In practice you'll have to use e.g. Jitsi with an USB headset on a > portable computer. Not exactly painless, and it opens you up to > system compromises. > > If anyone is aware of suitable dedicated hardware, I'd be thankful > for pointers.
You've reminded me of an episode of the RiskyBusiness podcast, I was listening to a few weeks ago with the grugq. He was talking about the small USB powered device the "TPLINK MR11U" or "TPLINK 3040". [1, 2, 3] He does talk exactly about the same issues - seperating your devices (in his case a laptop) from the GSM network using a portal device. He use is however a laptop, not a mobile device. But what he talks about is figuring out what you need to defend yourself against. I was listening to this thinking, if its so easy (The Grugq is using it! It must be secure!) then why isn't everyone using one? I have one on order from a trustworthy Chinese trader on ebay. ;) What I also thought was interesting was his *recommended* approach was buying a pay-as-you-go phone, presumably closed platform, with closed firmware. Secondly his choice of mobile device was *an iPad*! Seriously though, his advice was interesting. Has anyone else heard it? I'd like to hear opsec peoples' opinions. Hope that helps. Bernard [1] http://risky.biz/RB285 or http://media.risky.biz/RB285.mp3 (it starts at ~ 28:00 mins). [2] http://www.amazon.co.uk/TP-LINK-TL-MR11U-Portable-150Mbps-Wireless/dp/B0098AU7HY [3] http://www.amazon.co.uk/TP-Link-TL-MR3040-Portable-Battery-Wireless/dp/B00842KJOS -------------------------------------- Bernard / bluboxthief / ei8fdb IO91XM / www.ei8fdb.org
-- Liberationtech is public & archives are searchable on Google. Violations of list guidelines will get you moderated: https://mailman.stanford.edu/mailman/listinfo/liberationtech. Unsubscribe, change to digest, or change password by emailing moderator at compa...@stanford.edu.
