In June 2013, former CIA staffer Edward Snowden handed over two top-secret documents to the British "Guardian" and the American "Washington Post".
On June 5, the British "Guardian" first threw the first public opinion bomb: the US National Security Agency has a secret project code-named "Prism", which requires the telecom giant Verizon to turn over millions of users every day. call log.
On June 6, the Washington Post immediately threw a second bomb: in the past six years, the National Security Agency and the FBI have accessed the servers of nine Internet giants, including Microsoft, Google, Apple, and Yahoo, to monitor the Confidential information such as emails, chats, videos, and photos of U.S. citizens.
At this point, American public opinion was in an uproar.
The chats of those lovers, the top-secret business information in the business field, the private photos of actresses from all walks of life... Only you can't think of it, and no National Security Bureau can't get it. The absurd plots in the movie "The Truman World" are staged in the real world, and the actors are the ordinary people around you and me! With the advent of the era of mobile Internet, mobile phones that are almost inseparable make our privacy more vulnerable to eavesdropping.
In June of this year, "Whistleblower" Snowden had the following conversation during an interview with NBC Nightly News anchor Brian Williams.
Ryan Williams: If the NSA is interested in me and my life, what can they do with my iPhone? Can it be turned on and off remotely?
Snowden: They can do more than that. They can continue to control your phone when you turn it off, activate your phone's microphone, and monitor your every move.
Immediately afterwards, some interested computer security experts verified the content of Snowden's revelations, and found that he was not arrogant and indeed technically feasible.
Eric Macdonald, an electronic hardware engineer in Los Angeles, said that if the NSA computer hackers had implanted some kind of rogue software in the phone of the monitored object, when the mobile phone user turned off the power of the mobile phone, the mobile phone would not really shut down, just It entered a low-power mode that looked like it was powered off, with some of the phone's key communication chips still running in the background.
This "playing dead" state of the phone allows hackers to continue to control the phone, such as sending commands to the phone, activating the microphone, and monitoring.
After the phone enters low power mode, the screen is completely black, and you will not respond to any keystrokes, and it looks like it is turned off. But the processor is still working, or it will work intermittently. If you're not a professional, there's no way to tell if your phone is actually turned off.
So, what channels did hackers use and what techniques did they use to successfully eavesdrop? And how can mobile phone users prevent themselves from being eavesdropped? Xiaobian here to teach you how to prevent eavesdropping! What channels do hackers use to monitor?
1. GPS network channel
The accuracy is very high, which can be accurate to ten meters or even a few meters. It needs the support of the mobile phone hardware GPS template, and now most mobile phones have this template. From the hacker's point of view, the GPS-based positioning method uses the GPS positioning module on the mobile phone to send its own position signal to the positioning background to achieve mobile phone positioning.
2. WiFi channel
Like our mobile phones, in fact, each WiFi hotspot (router) has a unique address. When the mobile phone turns on the WiFi, it will scan and collect the WiFi signals of the surrounding routers (regardless of strength, whether it can be displayed or not, as long as there is , can be scanned), and upload their location information to the server to form a huge hotspot location database. The server then retrieves the geographic location of each wifi hotspot, and then calculates the geographic location of the mobile phone according to the strength of the signal. This is wifi positioning.
The orientation is calculated through the Wi-Fi hotspot, and the multi-user indoor positioning is also very accurate. Usually, the management software in the mobile phone is very sensitive to the positioning authority of the APP, because they can still roughly locate your position when the GPS is turned off, which is calculated by the signal and Wi-Fi hotspot.
3. Base station positioning
Base station positioning is generally ground positioning, which is positioned through mobile phones. Generally speaking, as long as you calculate the signal difference of the three base stations, you can determine the approximate location of your mobile phone. That is to say, as long as your mobile phone has a signal, others can track your location by checking which base station has contacted your mobile phone.
And each SIM card has a unique identification code (phone number), when your mobile phone is connected to the base station signal, this data will be recorded and uploaded. As long as others know which base station your mobile phone has connected to in the recent time, they can also determine the geographical range of the mobile phone, and the accuracy can reach several hundred meters.
While removing the SIM card may deter most cybercriminals, each phone carries a unique identifier that can be detected by devices like the Stingray used by police and the military, or by 2G fake cell towers set up by the NSA.
What if you just remove the SIM card without shutting it down?
Because as long as the mobile phone is turned on, it will connect to the base station signal to obtain the network by default, so that the base station obtains the ID information of the mobile phone, and then determines whether there is a SIM card.
If there is no SIM card, at most, others cannot find the mobile phone directly by monitoring the number, but they can also find out where the mobile phone has been turned on by investigating the mobile phone ID associated with the number, so as to track your location information.
Do you suddenly feel a little scary?
Having said that, as long as we unplug the SIM card after shutting down, will it not be located?
and! Do not! Yes! In the name of the people from a hacker's point of view:
It is also feasible to eavesdrop on the phone when the phone is turned off. When the battery is not unplugged, the mobile phone may be in a "false shutdown" state. For example, everyone has experienced the alarm clock when it is turned off.
What techniques do hackers use to eavesdrop on cellphones?
1. Hang up monitor
This method cannot be detected by any anti-monitoring technology. It is a national-level monitoring technology and is applicable to any monitoring method (landline telephone monitoring, mobile phone monitoring). Are you a commercial spy? If not, this kind of monitoring method will not be used on you.
2. Digital GSM mobile phone blocker
This monitoring device is mostly used by professional forensic monitoring personnel such as commercial spies. The application range covers a wide range, including: specific number lock monitoring, interception of calls, text messages, audio lock (it is useless to change the number because the voice audio is locked), scan the call content in a specific area... and other monitoring functions, any anti- No monitoring technology can detect it.
3. Spy satellite monitoring
The military-level monitoring method of a specific country has powerful functions and is mostly used in national security systems, which cannot be detected by any anti-monitoring equipment.
4. Implant chip and implant software to eavesdrop
At present, the monitoring tools available to the general public include implanted chips and implanted software. The implanted software is different from the previous chip monitoring technology. It does not leave any data in the mobile phone. It is fast to install and has powerful functions. It does not ring or vibrate from time to time, and the current anti-monitoring equipment cannot effectively detect it.
How do you find out that you have been bugged?
If the following points are met, don't hesitate, you are being eavesdropped.
If you only meet a few items, you need to be careful!
1. The mobile phone was not bought by yourself, such as a gift, or it has disappeared for a while
Mobile monitoring needs to be "installed" with the mobile phone of the "monitor". If the installation takes time, it will take about a day to implant the chip, and it will take about 3 to 10 minutes to implant the software, so if your mobile phone has disappeared for more than half an hour , even if this condition is met.
2. The mobile phone is occasionally funny, and occasionally the button response will be slower
If the mobile phone is implanted with a chip, while the "eavesdropper" is listening, when you pick up the mobile phone, whether you are playing GAME or dialing a phone, the first button you press will be delayed by 1~2 seconds. This is not the case with implanted software.
3. Strangers appear in your address book
If there is, the phone may be the "eavesdropper", which is the phone number used for the callback, that is, the "eavesdropper" dials this phone to eavesdrop. Although he can't know who the other party is, he deletes him. Just drop it.
4. Communication costs skyrocketed
Mobile phone eavesdropping has a function that can "actively" send text messages to "eavesdroppers" without your knowledge, and there will not be any records of text messages sent on your phone, you can only check it from your monthly bill. , If you don't pay the bill yourself, the person who pays it is even more suspicious.
The content of the text messages you send to the "eavesdropper" is: incoming and outgoing calls (who calls you, who do you call), text messages, text messages sent to you by others, and you will automatically send one to you after you receive them." The eavesdropper", the text message you send will be automatically sent to the "eavesdropper" when you send it. However, this function can be turned on or off. If it is turned on, the SMS fee will skyrocket.
5. The SIM card enables the three-way calling function
To monitor the content of the call, it is nothing more than that while you are talking on the phone, another person calls in, which usually turns into a call-in or the phone is busy; but if your mobile phone has a three-way calling function," The eavesdropper "can listen directly to the content of the call as soon as you dial in, and you don't even know it. It is suggested that it is best to call your mobile phone company to check whether the three-way calling function has been enabled by "someone". If this function is turned off, although it is impossible to know who the "eavesdropper" is, at least the content of the call is not Will be bugged again.
How to prevent eavesdropping?
1. Cut out the battery of the mobile phone
In theory, if your mobile phone has no energy supply, it will no longer send out signals to communicate with the outside world. However, this method has basically failed. Most mobile phones on the market have non-removable batteries, which are extremely inconvenient to operate.
2. Strengthen Yourself: Avoid Malware
Malware can only spy on you after installing a malicious app. Therefore, as long as you are more careful in daily use, avoid opening SMS attachments, refuse to install apps from unknown sources, and pay more attention to installed apps, you should be able to avoid malware invasion.
3. Virtual positioning: Make fake locations to confuse the other party. Many mobile phones now have a "traversing function" that can locate the mobile phone to "various locations" to confuse the stalker.
Original link: https://www.leiphone.com/news/201710/11IT2Ae42Wc5QPFh.html?utm_source=debugrun
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