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38

This started as a comment reply to @user10008 but got too long... Even after the towers are all upgraded, the carriers can't immediately switch off 2g service for a number of reasons. The biggest issue there is that not everyone upgrades their phone frequently; in particular this is true of people who use it as just-a-phone or an emergency-use-only-phone. ...


33

In order to make a cellphone tower UMTS-capable, various hardware upgrades need to be made to it. This costs money. For that reason, many cellphone towers, especially in rural areas, have not been upgraded yet. As long as there is not near-100% UMTS coverage, cellphones will still need to support a pure GSM connection to ensure that the user has ...


22

The telecommunications service provider (your cell phone company) has to transmit the SMS and MMS messages to their recipients; so yes, the provider has to store them, however briefly. Most providers retain messages for varying, not-so-brief, periods of time. Search [sms carrier retention period].


17

If a phone is not on the network messages must be stored until they can be delivered, so SMSCs and MMSCs have storage capabilities. SMS and MMS messages can be retained indefinitely on the system or they can be exported to an archive if the carrier chooses. If governments are storing phone call records they are almost certainly retaining SMS and MMS ...


13

Sniffing and recording the signal is certainly doable, since that's what both cell phones and base stations do all day long. Now the tricky point is that communications are encrypted, and decrypting the data from the outside can prove tricky. "3G" is a wide term, but (normally) 3G communications use the block cipher KASUMI. The best known cryptanalytic ...


12

First things first. Since your package was tampered with, I do not expect you to have any details of the phone like the IMEI number, etc. Register a complaint with the website that you purchased the phone from. Even if you go to the police, they are going to ask you to talk with them first anyway. I suggest you talk to a senior customer care executive, ...


10

The hardware tool that is suited to his is the Universal Software Radio Peripheral (vendor site). You can get a leg up on decoding the transmissions by looking at the work done for the OpenBTS system. So, hardware-wise it's commodity equipment, though a few thousand dollars because it's not very common. Software wise, the groundwork is already there to pull ...


10

Regarding your dad's iPhone, there's nothing to worry about. This is just an automated attack against Wafer GSM-AUTO (SMS-capable) devices. The Wafer GSM-AUTO is a very simple Microcontroller. You can think of it as a remote power switch. It control anything from a security door switch to a normal light switch. I'll try to translate the commands for you ...


10

For the most part[1] they are encrypted, but not sufficiently enough to be considered as safe, tap resistant encryption. GSM uses 64-bit A5/1 encryption that is weak, to say the least. $15 phone, 3 minutes all that’s needed to eavesdrop on GSM call article from ArsTechnica covers it pretty well IMO, if you care to read more about it. However, it also ...


7

Yes, all GSM calls use an A5/1 stream cipher. It has been found that this is fairily easy to decrypt using a Rainbow Table. Additionally, the FBI admits to intercepting all phone conversations in the US. So yes, it is encrypted, and cell phone companies don't give a damn about your privacy. If you care about privacy, you should use RedPhone and ...


7

It sounds like the technology you experienced is a call-agent blocker. These systems are designed to reduce fraud by not giving the call center your information, instead they transfer you to a computer who will process your pin, then if correct, will transfer it back to the calling agent. In this way, the agent can verify your identity without ever hearing ...


6

No, there is no way to communicate without being jammed. You can create redundancy so that the system has several ways of communication. If the system detects that any one way is jammed it can send an alarm another way. Another possibility is to send the alarm from an external system. Your alarm system regularily contacts the external system sending a ...


6

Yes if an attacker can create a fake basestation then they can effectively emulate the phone network and intercept calls which are made via that basestation. This is obviously a relatively local attack (e.g. you need to be close enough to the fake basestation for it to be the strongest signal available) Some time ago the costs of doing this were pretty ...


6

Jamming is the radio equivalent of shouting. The jammer drowns your communications under a lot of noise. Defence against jamming usually is a combination of the following: Power: speak louder. I.e. increase the power of your radio-emitting apparatus, so that it will take more noise to drown it. Of course, this increases energy consumption and heat ...


6

Yes, You can build a GSM basestation using an USRP and the OpenBTS. What you do, is announce that you are a basestation for i.e. AT&T, and if you have better signal power than other basestations in the area, AT&T cellular phones will start connecting to your basestation. Normally, the mobile phones would encrypt the sent data using keys that only ...


5

Defcon has had a few presentations on this subject. An active attacker can turn off encryption altogether, never mind just changing it. Also there is an open source program available just for this. I will edit this with the link when I find it. Software: http://openbts.sourceforge.net/ Antennas https://www.ettus.com/product/category/Antennas RF ...


5

Though the details are not published yet, the currently known information points at the following: some sensitive operations are protected with some encryption and a MAC, both relying on carrier-specific choices of algorithms and key lengths. However, some carriers apparently rely on DES whose key size is relatively small (56 bits), making key recovery in ...


5

Jamming is used either by fools or by clever professionals. The jammer can be triangulated by professional-level direction-finders (see source of this answer for a sample link) in half no time (unless special steps are taken by the attacker) What is jammed cannot be eavesdropped (okay, it's not as easy as that, but will suffice for the simplest case) ...


5

Yes, but I don't know if you will be authorized to do it. There should be an IMEI number on the tampered box. All you can do is take it to the nearest police station and file a case for it. Hopefully they will track down the thief by it. Above all, you should not have accepted the package if it was tampered. Now, File a case on the website and I am sure ...


4

The most commonly deployed 2G (GPRS/EDGE) ciphers have now been publicly broken, and the evidence indicates that they were once again intentionally left weak by the mobile industry designers. See this news coverage: Researchers Hack Mobile Data Communications - Technology Review Codebreaker Karsten Nohl: Why Your Phone Is Insecure By Design - Forbes ...


4

First of all, what do we need to clone a GSM SIM card? We need to extract the private key, Ki, from the SIM card and then use it to fake/forge a new one with the same number and subscriber ID. Here's why it's difficult to satisfyingly answer your question: GSM uses a cryptographic suite called COMP128. The biggest problem with COMP128 is that it's a ...


3

This is certainly possible. And many such devices do exist. Whether this is legal is not a question for this site, but I would strongly suggest talking to a lawyer in your area who deals with this type of law. There's a really, really strong possibility that local laws prohibit exactly what you're talking about. In particular, the simplest technique is to ...


3

It depends on the version of your SIM card, but normally if it's not older than 10 years (this is about the time when all SIM cards were starting to use 3DES instead) you should be alright. This depends unfortunately entirely on your carrier and there is no easy way to found out. You can check this yourself according to the very extended article on ...


3

The following presentation from Blackhat, is exploiting the Intel Centrino drivers in Microsoft Windows. Remote and Local Exploitation of Network Drivers Attacking a USB modem in the similar way, in contrast to the Intel Centrino attack, is much more unlikely. The attacker is most likely stuck at the TCP/IP layer, where in the wireless case, the attacker ...


3

To answer your exact question, to the best of my knowledge no security vulnerabilities from USB dongles have gotten any attention in the past years. I guess that was what you're looking for? However, there are known cases of rogue USB devices that are used to backdoor computers. Some security companies doing penetration testing and social engineering ...


3

Actually, GSM uses "A5", which is not one algorithm, but several. The initial GSM standard dates from the late 1980s, and had to work on hardware available at that time. A mobile device using what was considered the standard secure block cipher algorithm at that time (3DES) would have been too bulky and drawn too much power to be considered "mobile", even in ...


2

who is the governing body responsible? I've been out of the industry for a few years, but I'd be surprised if anything has changed since I worked there. There is no formal constraints on the content of the sender id, it's really very much up to the Telco. In the UK Ofcom extended their recommendations to providers, (you can read the ofcom stuff here - ...


2

Yes, but you need a transmitter too, basically, you build a base station and MITM the connection by getting phones to connect through it (usually by lying and saying you are some major network), you then have to actually handle call routing and stuff as the base stations do.


2

A GSM phone will happily talk to any "base station" in range, and will happily talk to the one which claims to be the most powerful. It is a feature of the protocol: the phone will not necessarily link to the base station that it receives the most clearly; a station can simply say "talk to me ! I have dibs on the connections !" and the phone will use it as ...


2

In case you are not aware, many people have considered GSM security to be weak and there are freely available rainbow tables for decrypting GSM. Any determined eavesdropper with off the shelve equipment will be able to listen to your calls. You might be interested in reading this Are phone calls on a GSM network encrypted? But if you are worried about the ...



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