December 11, 2023
SIM Interposer Provides Legally Questionable Unlock For All iPhone 4s [Video]

SIM Interposer Provides Legally Questionable Unlock For All iPhone 4s [Video]

Posted March 17, 2011 at 2:04am by iClarified · 74339 views
Gevey has released a SIM Interposer which can unlock the iPhone up to iOS 4.3 by force activating the baseband using the emergency dialer.

A blog post by Laforet explains that the SIM Interposer works by adding a EEPROM chip to your SIM card just like a TurboSIM. You then call 112, a number that can be called from any GSM phone, free of charge, with or without a SIM card on any compliant network. Once the call connects you hang up then toggle Airport mode on and off. When the network connection resumes you will be unlocked.

What does it mean to unlockers?
1. It works if A.your network handles 112 calls properly according to the GSM standard; B.they are tolerant to TSMI spoofing and does not actively validate your SIM again for incoming calls.

2. Unlike its ancestors, the i4 SIM interposer is not a drop-in-and-forget device. The exact precedure must be performed should the device restart, lose reception for an extended period of time or move to another PLMN. In all these situations the TMSI expires and has to be obtained again. Theoretically it is possible for a daemon to automate the process similar to ZeroG, but that only makes thing more convoluted.

3. It is, without question, unethical or downright illegal to use the technique anywhere 112 is a legitmate emergency number. Not a huge issue in China where the number is only used for informative purposes and the networks cannot be bothered to fix the issue.

4. All firmware/baseband combinations for the i4 up to iOS4.3 are vulnerable, however the exploit may be patched in any future software updates or via the carrier. If apple can influence providers to block Cydia it is not impossible for them to press them to fix the exploit. The only way to permanently unlock your baseband is NCK.

5. SIM interposer should not harm your phone hardware, however your network could request IMEI and identify your device during the emergency call. Your identity cannot be faked and it is possible that they will ban your account. There is a reason why SIM cards remain legally the property of the service provider: you are not supposed to tamper with them without breaching contract.

6. Notwithstanding all the problems, SIM interposer does not cause any battery drain since it is only active transiently, nor would it cause signal loss because it does not change cellular transmission other than the initial validation step.

Laforet concludes by saying that the $50 mod can be unreliable and is legally questionable. If you are desperate for an unlock it may be worth a try. Otherwise Laforet suggests you wait for the 40-bit NCK hack by the iPhone Dev-Team.

Read More [via Singularity] [via MuscleNerd]

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Thavisha - July 17, 2014 at 11:23am
I have an iphone 4s that is working with this device, and can someone please let me know, wheather if i update my software, will it malfunction?
Narssimha - March 18, 2011 at 2:00pm
Gents pls let me know how to get EEPROM CHIP in middle east UAE
Captain Sensible
Captain Sensible - March 18, 2011 at 8:01am
Waste emergency services' time to unlock your phone? Come on guys, let's get some perspective on what's important in this world and not mess things up for others.
Mor - March 18, 2011 at 10:36am
there's no waste here. you just call it for 2 seconds no one needs to answer in such a short time so there's no waste at all. It just has to connect the network that's all.
Captain Sensible
Captain Sensible - March 18, 2011 at 1:19pm
When I had to (genuinely) call the emergency services last weekend the call was answered within half a second. No ringing. No delay. Start wasting their time with crap like this though...
mor - March 18, 2011 at 1:47pm
not where i live so i am fine.
xdrive - March 17, 2011 at 3:24pm
what is this? is this kind of a sim attachment again? like the ones for 3g iphone before? attache some chip to the micro sim?
mor - March 18, 2011 at 10:37am
yes exactly...
Mor - March 17, 2011 at 6:57am
Can someone explain me this part? 1. It works if A.your network handles 112 calls properly according to the GSM standard; B.they are tolerant to TSMI spoofing and does not actively validate your SIM again for incoming calls. What should i hear if I call 112?
Xpress - March 18, 2011 at 10:42am
..ti all depends on Country you are..... here (Angola) 112 does not work at all... !!!
DanCJ - March 17, 2011 at 6:51am
$50 for a dodgy unlock?? Can you not just pay your network for an official unlock? My official unlock only cost me £15.
FARP.Thor - March 17, 2011 at 8:27am
And what operator is that? Where did you buy the iPhone? This solution is valid for users like me, that have a iP4 that was bought in the US and, therefore, locked. Operators in Brazil tell me they can't unlock it, it has to be done at AT&T. If you managed to have your phone unlocked via Carrier, I bet you bought it from a store in your country.
DanCJ - March 17, 2011 at 8:47am
I got mine from an Apple store in the UK back when O2 had exclusivity. They charge £15 to unlock pay as you go phones, and they'll do ones on contract for free - but you're still bound by the contract.
Bernardo - March 17, 2011 at 10:50am
Did you unlock yours? How? Mine is 02.10.04 and still locked. I wish to get it the factory unlocked. I tried to call AT&T and Apple many times ask them to unlock my iP4 even if the charge me to pay a fee to have it unlocked.
DanCJ - March 17, 2011 at 11:12am
With O2 there's a standard online form you can fill in to unlock for £15. They do something behind the scenes and then the next tine you connect your phone to iTunes it automatically unlocks. Sounds like AT&T don't do that
Rod - March 20, 2011 at 1:28pm
Even AT&T doesnt unlock you phone here in the US. Regardless if you purchase without a plan.
MINH - March 17, 2011 at 3:07am
GEVEY Sim will be available for sale after March 18th or 21st.
Rahil - March 17, 2011 at 2:53am
I'm from India n i want it to unlok my I4 at what time gey vey sim available.
Yankeet - March 21, 2011 at 3:14pm
Dude if it wotks then plz lemme know e1 i stay in india ,mumbai..or plz mail me at or plz call me at 9664463862 if u can thankyou....
Rahil - March 17, 2011 at 2:50am
Gey vey now available or what wher to buy it.
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