a standard developed by the European Telecommunications Standards Institute for the second generation of digital cellular networks, used by mobile phones. It is the default global standard for mobile communications.

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22
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3answers
4k views

A security concern I dicovered with simcard devices

Well, it all started when I wanted to take the sim card out of my tablet and I was about to shut it down so that I could take the simcard out. But then a thought raced through my mind, "What if I take ...
1
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3answers
173 views

Can bad guys record phone conversations without the carrier's knowledge?

I know that, in most of the world, phone conversations are transmitted as digital data (whether frames in circuit switched protocols or packets). I know that several companies offer products which ...
1
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0answers
162 views

GSM mobile messages with the first octet 01000000

In GSM networks, it is found that there are so many mobile phone messages (uplink) with the first octet 01000000. For example, the 28-octet message is: [64,32,238,176,168,33,236,7,11,43,43,43,43,43,...
1
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0answers
5 views

GEA3 direction clarification

GEA3 (and 4) stands for GPRS Encryption Algorithm. It's specified in 3GPP TS 55.216 (at least used to, until some idiot forced them to hide it because of "export restrictions" or some crap like that). ...
4
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2answers
81 views

Difference between “Unknown” and “Hidden” Caller ID

I remember the times when I had an old Nokia phone as my main; there was some weird behaviour with Caller ID which was strange for me. When somebody with subscription to "Hide your number" service ...
9
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1answer
379 views

Hacking/Sniffing/recording GSM like Karsten Nohl

For a course at college, I wanted to reproduce the attack on GSM shown in this video by Karsten Nohl: https://www.youtube.com/watch?v=0hjn-BP8nro. From what I understand he used an USRP radio to ...
3
votes
0answers
28 views

In mobile, can “Early Media” be sent from the phone?

Early Media, aka in-band information, is sent from the network to the calling phone in some circumstances, to provide alternative tones or extra information about the status of the call. In GSM this ...
1
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0answers
177 views

SS7 exploit on the wiretapping part

Wondering if there are info/source code/guide on the SS7 wiretapping part (SMS interception). I had a look on the track any mobile by a German researcher, and on PTsecurity about how the structure ...
13
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7answers
5k views

Strategies against jamming attacks?

We have some devices which are designed to use standard frequencies/protocols, such as GSM, CDMA, GPS, Wifi and Bluetooth, among others. While our focus is not thought to be used for high-profile ...
0
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2answers
57 views

Best way to keep cell day to day phone calls private - is VOIP better?

This question is about preventing eavesdropping by hackers, thieves, or other smart people collecting information for shady purposes. Is it better to buy a smartphone and install a VOIP service on it ...
1
vote
1answer
24 views

Would a recording of a complete GSM session provide a proof of authenticity?

Hypothetical question: suppose I had a OsmocomBB phone modified to record all transmission done over GSM including encryption keys used during the communication. If I made a call and recorded all data ...
0
votes
2answers
91 views

Is there a way to uniquely identify a mobile device through packet sniffing?

I need to uniquely identify a mobile device using the "ping" packets that it transmits to cellular towers regularly, in an area of interest by installing a packet sniffer at that location? I only need ...
2
votes
1answer
134 views

Capturing text messages on the fly

Suppose your phone is not connected to any network. You are sitting in a cafeteria with 50 other people, everyone is communicating to each other via text messages. Is it possible through any device or ...
1
vote
1answer
74 views

Bought used computer with working GSM card [closed]

I recently bought a used computer from a company. They are buying lots of computers from big companies and they refurbish them for resale. Today I discovered that my computer has an installed SIM card....
2
votes
3answers
557 views

Is it possible to protect against rogue mobile base stations? [closed]

I just read the answer to this question Mobile numbers capture and transmit data and it sounds surprisingly simple for calls/SMS (and data?) to be intercepted by a fake base station. From what I ...
3
votes
2answers
601 views

Airprobe and kraken related questions

I'm setting up test machine for my engineer work, to check GSM security and SMS interception. I already have an N210 and read a lot of documentation. There are some questions I have but can't find on ...
9
votes
1answer
491 views

Getting strange texts to an iPhone #PWD123456#00X

My dad is getting strange SMS texts to his iPhone 4 Some examples: #PWD123456#WHL003=2308480298 #PWD123456#WHL004=2398480389 #PWD123456#WHL002 #PWD123456#WHL002 #PWD123456#STATUS? #PWD123456#OUT1=...
31
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5answers
16k views

Are phone calls on a GSM network encrypted?

When I make a call on my cellphone (on a GSM network), is it encrypted?
12
votes
2answers
38k views

How to spoof a cell phone tower (cell site, base station) — homemade IMSI-Catcher

An answer to a recent question has given me an idea for a school project (security CS program). Also, an active attacker (with a fake base station) can potentially force a mobile phone to use ...
4
votes
2answers
767 views

Is a fake base station needed for IMSI catching?

If you read about cell phone tracking it looks an IMSI Catcher always uses a fake base station the get the phones IMSI. I don't understand why this is necessary. Couldn't they just passively read the ...
-2
votes
1answer
74 views

How can I know if any cell phones other than a given set are turned on in the nearby area?

I am searching for a solution to identify phones simply by the signals it emits. Imagine a signal receiver in a room, then I want to know which people are using phones nearby. I don't care what they ...
1
vote
1answer
84 views

Is originating number tied to an SMS from a mobile phone?

I've been working with an SDR (software-defined radio) as part of a computer security class project. We've been wondering if, let's say a mobile phone associates with the SDR (which is operating as a ...
2
votes
3answers
207 views

Is it possible to jam just one persons Cellphone but keep all other working?

I know devices that are jamming everyones Cellphones in a radius of X meters but this is only distracting the frequency cellphones work on. This is not very handy. Is it be possible to jam just one ...
3
votes
0answers
818 views

Cellular encryption algorithms currently in use globally

I have been doing research on the available encryption algorithms used by commercial mobile providers worldwide, and would like to know if the following list is complete: Algorithms for voice ...
18
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4answers
11k views

Are SMS,MMS stored on the network service providers' servers?

Are SMS and MMS sent via a mobile phone stored on telecommunication service providers' servers before passing them to the recipient? Does it depend on the country or does every network service ...
0
votes
1answer
594 views

How do I get Kc from my SIM card?

Since listening to a few Defcon talks on SIM cards and, more recently, the NSA Playset, I've become interested in GSM. This page gives a fairly good tutorial on getting Kraken set up, but apparently ...
11
votes
1answer
9k views

Mobile numbers capture and transmit data

will it be possible to build a low cost hardware/software device which can capture mobile numbers within a specified radius and then use that information to transmit an sms to those numbers? From what ...
0
votes
1answer
54 views

Is it possible to make a different encryption for a phone communication?

I wanted to know if maybe it's possible to make a phone communication more secure than the current A5/1 (used for GSM). Or maybe create a special tunnel between two phones. I mean like an ssh ...
32
votes
4answers
7k views

Why is GSM still used?

GSMs vulnerabilities have been known a long time now. UMTS was supposed to fix those problems. Why is GSM still used?
5
votes
1answer
154 views

What is the proliferation of IMSI Catchers?

We know that IMSI-catcher detectors such as the Android-IMSI-Catcher-Detector project exist, but has anyone done a field study across various parts of the world as to how many there are and where? ...
1
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0answers
85 views

Possible to use Cellular encryption data to validate Geolocation?

I need offline-verifiable, time stamped, GPS signals or its equivalent. Since cellular protocols include time stamps, encryption keys and other data, perhaps it's possible to re-use this ...
1
vote
2answers
2k views

Can someone listen GSM calls with RTL-SDR dongle if A5/1 cryptography is successfully cracked?

Can an attacker listen GSM calls in clear audio form (real time) using RTL-SDR dongle if he/she has powerful-enough hardware to crack the A5/1 crypto scheme in countries where no more secure ...
0
votes
1answer
56 views

In GSM is it correct to say A8 uses the random generated by the Auc and Ki to generate Kc?

In GSM is it correct to say the AuC uses A8 algorithm with as input a nonce and Ki to generate Kc used for encryption communication between the subscriber and base station? If not how is Kc forwarded ...
0
votes
1answer
98 views

Is it possible for someone to send messages from my phone and seem like if I send it to them? [closed]

Ok so there's this guy who pays my iPhone6 and lately it's been sending messages to him as if I was the person who typed it but it wasn't me... Does anyone get me? Someone please help!!
5
votes
2answers
94 views

Where does the GSM A5 key come from? Why isn't DH used?

I've read this article about NSA allegedly stealing SIM cards from Gemalto which states: After a SIM card is manufactured, the encryption key, known as a “Ki,” is burned directly onto the chip. A ...
13
votes
3answers
6k views

Smartphone / GSM Sniffer

This question would be in the category of SmartPhone Sniffers. So we have sniffers that can show the packets that are being sent across a wired or wireless (802.11) network. I am just performing a ...
0
votes
1answer
159 views

Is there any secure way to transfer data between mobile phones without Internet? [closed]

Assume that I don't have any Internet access in my country. The only thing that I have is a mobile phone with a 3G or 4G SIM card inside. The mobile operator didn't provide any Internet access also. ...
0
votes
3answers
330 views

Can my GSM network operator figure out the name of the Wi-Fi access point I am connected to?

I recently saw a film where the police were able to locate where the criminal was because the GSM network operator knew the name of the Wi-Fi access point the phone of the criminal was connected to ...
1
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2answers
1k views

GSM A5/1 encryption: Key management

I'm currently studying the A5/1 algorithm used for GSM encryption. I understood how thanks to the symmetric private Key and a public counter frame one can encrypt the communication between A and B. ...
7
votes
2answers
820 views

Is there a way to notify me when my Android phone connects to an unencrypted GSM network?

As far as I know when a phone connects to a GSM (2G or 3G) network, the connection is encrypted. When I get in range of let's say an IMSI Catcher, I imagine this connection will not be encrypted in ...
1
vote
2answers
340 views

Is there man in middle attack when using mobile phone calls?

My question is about the encryption between me and my mobile operator. My mobile operator uses A5/1. I use Samsung. Sometimes I see the symbol G on my phone which means GPRS. I don't know whether it ...
6
votes
3answers
4k views

Is it possible to track a missing brand new phone? [closed]

I ordered a Nokia phone online and it turned out that the packet had been tampered and the phone was missing from the package. Obviously it does not have a SIM card, etc. I assume someone stole it ...
1
vote
3answers
2k views

How does a GSM triangulation work? [closed]

A have always been told that to get a geolocation of mobile phones there is the need 'ping' it with at least three cells. So actually, a standard and basic triangulation would just get from three ...
-1
votes
2answers
3k views

Can you listen to your last GSM call recorded when calling back a user?

My wife called a GSM/3G number abroad and the call was dropped. She called again and she could hear the whole conversation repeated with the other party but with blank period from her side of the ...
1
vote
1answer
476 views

Why does not GSM use any stream cipher mode (OFB, CFB)?

If I understand correctly GSM uses A5/1 stream cipher. My question is why doesn't it use a stream cipher mode like OFB or CFB?
5
votes
2answers
1k views

Is my SIM card vulnerable to DES cracking?

Srlabs have recently published article stating that many SIM cards can be exploited using vulnerability in DES: [...] While the option exists to use state-of-the-art AES or the somewhat outdated ...
5
votes
3answers
3k views

Which is safer, GSM or CDMA?

I have read in the past (no sure where) that unfortunately there exist illegal devices that permit crooks to eavesdrop on GSM mobile phone conversations. I recently also heard that some people had ...
3
votes
2answers
1k views

What to do when GSM/Wifi is jammed and ethernet cables are cut?

So.. There are household alarm systems (to defend against burglars) which send SMS/e-mail alerts if an intruder has been detected or an alert is trigged. However, Mobile networks can be jammed, and ...
1
vote
2answers
2k views

Fake GSM mobile number?

IMHO there was a Blackhat video about it, but cannot find it: Is it an existing problem that a mobile phone number could be faked? I mean when using internet banking: The attacker gained the ...
0
votes
2answers
2k views

Is it feasible to make an IMEI sniffer the size of a matchbox within EU legislation?

I want to produce a list over the GSM phones in an area. I don't care about what data goes back and forth, neither are the various conversations relevant. Most phones have IMEI (International Mobile ...