Protection against wiretapping of cell phone conversations. Experts warn that applications that protect against IMSI interceptors are useless. How to determine that a phone is being tapped

This App will Help you in Detecting "IMSI Catchers" (also called "Fake Cell Towers" or "Stingrays").

For several years the FBI and Local Police have been listening to our Calls and Reading our Text Messages, using so-called "IMSI-catchers". One Example of such a "Fake Cell Tower" is the "Stingray", which is produced in the USA.

"Stingrays" are Mobile Devices that simulate Cell Phone Towers, forcing nearby Phones to Connect to them. They can Identify your Phone, and possibly listen to your Calls. Without having to put a Spy app in your Phone!

These "Cell Spy" Devices can capture Information from All Cell Phones within Range, including IMSI Identity, Location, SMS Messages, Call Logs and Call content.
(IMSI stands for "International Mobile Subscriber Identity", which will Identify your Phone).

It is known that at least 53 Agencies in 21 States own "Stingrays".

Law Enforcement Agencies, Foreign Powers - and possibly Criminals - are using such "Cell Site Simulators" for Surveillance Purposes - without our knowledge.

"Cell Spy" Devices can be Hand-carried, or be mounted in Vehicles, Airplanes, Helicopters and Unmanned Aerial Vehicles.

During a Self Learning Process, the App will "learn" all Networks (Cell Towers, Base Stations) that are used by your Phone.

After the Self Learning Process - if this App should happen to Detect one of these "Cell Spies", you will be Warned by an Optional Sound and/or an Optional RED Screen. The simplest way to avoid being Listened In On, is then to turn off your Phone for a while, or at least to keep silent.

When the App Detects a Network that is not included in its Internal Database, it will Consult an External Database of Networks. If the Network is not Found there, it is assumed to be UNKNOWN.

Very Easy to Use
- Self Learning Process
- Periodic Checks for Networks
- Selectable Network Checking Period
- Logging of All Events
- Internal (Self Learned) Database
- Integration with External Database (OpenCellId)
- Optional Detection, Logging and Warning of "Unknown" Networks
- Even Attacks only lasting for a few seconds can be Detected
- Measurement of Duration of Attacks
- List of All Identified Networks
- Export of CSV File
- Analysis of Current and Historical Network Data
- Warning Level Assessment
- Support for GSM, UMTS/WCDMA, CDMA and LTE
- Battery Saving Design
- Using a "Passive" GPS Location Technique, to save power
- Internet Access is RECOMMENDED, but NOT necessarily Required
- Internet Access WILL Improve the Detection Quality of Unknown Networks
- Always Running in the Background, even when Phone "sleeps"
- Auto Restart at Boot Time
- Rooted Phone NOT Required
- No Special Phone/Hardware Required
- Also works on Tablets with SIM Card
- Lots of Answers to FAQs
- Info about "Fake Cell Towers", "Stingray", etc

After you have Opened the App the First Time, you should Start the Self Learning Process (which may take a few Days), and have the Phone with you at All Times - where ever you may be - in order for the App to LEARN about ALL Local Networks.

If you move to another place, you should Restart the Self Learning Process.

By using this App, you participate in the large collaborative community project "OpenCellID" - which collects the Locations of Mobile/Cellular Phone Towers, which now is a Database that contains almost 7 million unique Mobile/Cellular Phone Tower IDs. Use of this Database will increase the Probability of Detecting REAL UNKNOWN Cell Towers - and thus to Find "IMSI-Catchers" - and you can be an Active Part if it!

If you should NEVER Detect a "Fake Cell Tower" - you should consider yourself LUCKY - and NOT BLAME us!

Many problems seem to be caused by simple Misunderstandings. So if you have a problem - that cannot be answered by the FAQs Section of the App - please send us an Email - before you consider making a Bad Rating. Maybe we can help you. [email protected]

How can you listen to conversations on mobile phones, is it possible to protect yourself from this kind of attack, and how can a subscriber determine that his phone is being monitored?

GSM technology was initially developed and implemented taking into account the requirements government agencies by level of security. To maintain this security, most countries in the world prohibit the use and sale of powerful encryptors, scramblers, crypto equipment, as well as highly secure public communications technologies. Telecom operators themselves protect their radio channels by encryption, using quite complex algorithms for this. The choice of cryptographic algorithm is carried out at the stage of establishing a connection between the subscriber and the base station. As for the likelihood of subscriber information leaking from operators’ equipment, MTS claims that it is reduced to zero due to the complexity and controllability of access to facilities and equipment.

How can you tap phones?

There are two methods of listening to subscribers - active and passive. Passive listening to a subscriber will require the use of expensive equipment and specially trained personnel. Now on the “gray” market you can buy complexes with which you can listen to subscribers within a radius of 500 meters; their cost starts from several hundred thousand euros. They look like the picture on the right. On the Internet you can easily find a description of such systems and the principle of their operation.

Manufacturers of such equipment claim that the system allows you to monitor GSM conversations in real time, based on access to the site or database of the cellular operator. If there is no such access, then conversations can be listened to with a delay, depending on the level of encryption used by the operator. The system may also be part mobile complex to track and listen to moving objects.

The second method of eavesdropping is active on-air interference with control and authentication protocols using special mobile systems. Such equipment, despite its apparent simplicity (in essence, it is a pair of modified phones and a computer), can cost from several tens to hundreds of thousands of dollars. Working with such complexes requires highly qualified service personnel in the field of communications.

The operating principle of such an attack is as follows: the mobile complex, due to its closer location to the subscriber (up to 500 m), “intercepts” signals to establish a connection and transmit data, replacing the nearest base station. In fact, the complex becomes an “intermediary” between the subscriber and the base station with all the ensuing security problems.

Having “caught” the subscriber in this way, this mobile complex can perform any function to manage the subscriber’s connection, including connecting it to any number the attackers need, installing a “weak” encryption algorithm, or even canceling encryption for a given communication session, and much more.

An example of such eavesdropping is the events of the beginning of this year in the center of Kyiv. During mass protests against the Yanukovych regime, the crowd seized a car with SBU officers, from which they “wiretapped” the frequencies of the protesters’ radios and phones. What such equipment looks like can be clearly seen in the picture.

There is a third possibility for listening to conversations and intercepting mobile subscriber traffic. To do this, you need to install virus software on the victim’s smartphone. When installing malicious software, attackers can “independently” choose or cancel the encryption algorithm, unauthorized transfer (or destruction) of the subscriber’s confidential information, and much more.

How to determine if your phone is being tapped

It is impossible to directly determine whether the phone is currently being tapped, but it is possible to obtain indirect confirmation of some probability of this. Many models of old push-button phones even displayed a special icon (closed or open lock), which demonstrated whether conversation encryption was currently being used or not.

Modern phones do not provide this function. However, there are special applications for smartphones that can inform the user about the configuration of the settings of the current communication session, including whether his speech is transmitted openly or using an encryption algorithm. Here are some of them:

EAGLE Security

A powerful program to protect phones from eavesdropping. It allows you to prevent connection to a false base station by checking the signatures and identifiers of base stations. In addition, it tracks the location of stations, and if a base station moves around the city or periodically disappears from its place, it is marked as suspicious and the program notifies the user about this. Using the program you can also get full list applications that have access to the phone’s microphone and video camera, and also block unwanted software from accessing the camera.

The program helps to monitor any suspicious activity on the cellular network, including SMS that are sent without the user's knowledge. The program also evaluates network security in real time, shows which algorithms are used to encrypt conversations, and much more.

Android IMSI-Catcher Detector

Another software package that allows you to protect your smartphone from connecting to false base stations. True, it has a small drawback - the application is not on Google Play and you will have to tinker a little with its installation.

CatcherCatcher

CatcherCatcher, just like Android IMSI-Catcher Detector, allows you to distinguish a real base station from a false one.

In addition, MTS recommends using security applications, including encrypting conversations. For example, anonymous web browsers include Orbot or Orweb. There are also applications for encrypting telephone conversations, photographs, and many secure instant messengers.

Based on the SIP protocol. Today I’ll just show you a few useful programs that will allow you to avoid listening to your phone.

EAGLE Security

It is one of the most powerful applications for protecting your mobile phone from wiretapping. This program prevents any connections to false base stations. To determine the reliability of a station, a check of signatures and station identifiers is used. In addition, the program independently monitors and remembers the location of all base stations, and if it is detected that a base is moving around the city, or its signal disappears from time to time from its location - such a base is marked as false and suspicious and the application will notify the owner about this phone. Another one of useful functions programs - the ability to show which of the applications and programs installed on the phone have access to the video camera and microphone of your phone. There is also a function to disable (prohibit) access to any software you don’t need to the camera.

Darshak

This program differs from the previous one and its main function is to monitor any suspicious activity on the network, including the use of SMS, which can be sent without the permission of the phone owner. The application evaluates in real time how secure your network is, what encryption algorithm is being used at that moment, and much more.

This application also helps protect your smartphone from any connections to pseudo-bases. The only disadvantage of this program is that you will not find it on Google Play and if you still want to install it, you will have to tinker with this procedure.

CatcherCatcher

The CatcherCatcher program, like its analogues above, is engaged in identifying false base stations that attackers (or special services?) use as intermediate “intermediary bridges” between the subscriber and the real base station.

And finally, we recommend using special applications to ensure the security of personal conversations and data, including encrypting your conversations. Similar analogues are the anonymous web browsers Orbot or Orweb, for example. There are also special programs that encrypt your telephone conversations, photos, and many already use secure instant messengers.

In which we examined the principles of operation of such devices, their effectiveness, and also considered methods of protection. Let me remind you that these devices are widely used by both intelligence services and “bad guys.” They use design feature mobile phones - give preference to the cell tower whose signal is the strongest (to maximize signal quality and minimize your own power consumption). In addition, in GSM (2G) networks, only the mobile phone must undergo an authentication procedure (this is not required from the cell tower), and therefore it is easy to mislead it, including in order to disable data encryption on it.

We have already written that despite a considerable number of “protective” Android applications on the market, which should warn the user about connecting to an IMSI catcher, most of them cannot be called high-quality. In addition, such applications often lead to many false positives (usually due to insufficient technical qualifications of their developers).

Now at the USENIX conference they are going to present a report dedicated to this problem and fully confirming our conclusions. Applications for protection against IMSI interceptors were studied by a joint group of specialists from the University of Oxford and the University of Berlin technical university. The researchers tested the performance of five popular programs: SnoopSnitch, Cell Spy Catcher, GSM Spy Finder, Darshak and IMSICD, which have between 100,000 and 500,000 downloads on Google Play.

To conduct tests, experts created their own White-Stingray framework, capable of carrying out attacks on 2G and 3G networks. In fact, the researchers' development is a very “naturalistic” imitation of commercial IMSI interceptors.

Testing of applications has shown that they rarely notice suspicious activity and are able to detect only the most common and simple attack techniques. For example, applications record a forced connection downgrade or the receipt of a “hidden” text message that is used to determine the location of the device. But experts write that attackers only need to switch to another attack technique, and the applications will be practically powerless. Moreover, applications are hampered by the limitations of the Android API itself, with which little can be done.

“Currently, ICD applications on the market are easy to fool using simple bypass techniques as they are highly limited and do not have access to the underlying hardware of mobile phones. Therefore, you need to understand that ICD applications are not a silver bullet due to these fundamental limitations,” the experts write.