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How to Tell If Your Phone Is Hacked and How to Fix It

Michael has a Newcastle University Certificate in Cybersecurity and experience in combatting cybercrime.

Essentially, your phone is used to grow the hacker's business while they leave you to rake in the bills.

Essentially, your phone is used to grow the hacker's business while they leave you to rake in the bills.

12 Signs That Your Phone May Be Hacked

1. Unauthorised Activity

Does your phone switch itself off, open new apps inadvertently, accesses sites, or executes other activities by itself without your intervention? If your phone does not readily respond to the commands you give (like failing to turn off when you deactivate it) but often seems to be making other operations instead, this may be indicative that third parties are in control.

Aside from giving you the impression of having developed a life of its own, you may observe that certain changes have been made to the phone settings which you did not initiate. Alternatively, you may suddenly find you are no longer receiving messages or calls on your phone though you have not blocked anyone. This could indicate that a communication diversion has been created.

2. Changing Displays

You may also observe that the view of your browser or the way in which your apps are displayed has changed. This could be indicative of background installations and processes preventing screens or sites from appearing as they normally would.

This effect may resemble a phone's reaction when it is connected to a Bluetooth device where there may be visible changes on displays, sounds, and other features before the device fully connects. This is indicative that a foreign device or program is connecting with the phone, thereby creating loading time delays.

3. Suspicious Interferences

Watch out for multiple pop-up windows that appear on your screen with instructions to click on certain links or to download certain programs on your phone.

Another indicator is if your phone keeps disconnecting when you make calls or there are strange noises when you make calls. This could be due to a network connectivity issue. However, it could also be indicative of malicious hackers trying to gain access to the device's features and applications.

Echoes and suspicious background noises you have not experienced before could be indicative that someone else is listening in on the conversations. There are cases where electronic interferences continue even when the phone is not in use.

4. Slow Processing

Your phone may have slowed down considerably and you have to wait longer for apps to load, you find yourself constantly refreshing the browser or restarting your phone often.

One reason for this is third-party activities. Once a malicious program has been introduced into your device, it requires power to use applications such as your camera to record videos, collect and send data back to the hacker. This in turn slows down your other operations.

5. Strange Text or Voice Messages

Are there messages in your outbox that did not originate from you? Are people receiving text messages from your phone which you did not send? Have you observed unknown or foreign numbers recorded in your outgoing call history despite the fact that you did not make the calls?

It could be that hackers are using your phone as their calling device, or have forwarded your number to their customers for local or international dialing. Once the customer(s) pay the hacker for the service, they are connected with your phone for their outgoing calls. So essentially, your phone is used to grow the hacker's business while they leave you to rake in the bills.

The same applies to messages that appear as having been sent by you. You may also be receiving unusual or questionable text messages whose source is unknown.

Security should be maintained across all devices in your ecosystem

Security should be maintained across all devices in your ecosystem

6. Overconsumption

If your battery consumption has been going up lately it could be a sign that the phone is accessing multiple services. If the charge is short-lived and you find yourself recharging your device constantly, it could be a power-drain caused by a hacker's activities.

7. Data Overuse

Has there been an unusual depletion of data lately, especially one that cannot be accounted for? If you check and discover that an app is consuming an unusual amount of data, it could be a red flag as well, because that app may be tracking.

8. Increasing Service Charges

Another sign is if your phone bill is increasing inexplicably. If your device is being accessed by multiple services, there will be increased consumption of data leading to a spike in service charges that cannot be readily explained or accounted for. A second cause is that as you send your text messages, another program could be duplicating and forwarding them to the hacker through the server with the result that your phone bill keeps rising.

9. Malfunctioning

If the apps on your phone are not working as they usually would but appear to slow down or frequently malfunction, it could be because there is malware blocking normal operations. Basic tasks become difficult, including such activities as adjusting the brightness, contrast, volume, or even taking photos and videos.

10. Overheating

If your phone keeps heating up even when it is not in use, this may indicate that unknown background processes are executing and causing the phone to warm up. Mobile devices are not manufactured to overheat and they will typically have safety mechanisms to prevent this.

11. Spam Emails

Are emails sent through your phone constantly being flagged as spam in the recipients' accounts? This happens if filters recognize your emails as originating from a malicious source because there is an interceptor between your phone and the recipient. The emails you send go out to this intermediary who monitors them before they are forwarded further to the recipient.

12. Contract Termination Block

You may find that even though you terminate the phone contract with the service provider, you are receiving communication from them as though you are a continuing customer. Well, this may simply mean that their system has not been updated with your termination. However, it could also be due to the fact that the authorities have issued a mandate to the company stipulating that your contract should not be ended under any circumstances since your phone is under investigation.

Identify and uninstall all apps that you did not authorize

Identify and uninstall all apps that you did not authorize

How to Protect Your Phone from Hackers

1. Monitor Your Apps

Go through the apps that are currently installed on your phone. Did you authorize the installation of all of them or are there some that have been installed without your consent? Identify and uninstall all apps that you did not authorize. Also, uninstall all apps that you are not using on a regular basis, and those that are consuming unnecessary data.

Ensure that the apps that you retain on your phone are safe and reliable. Your apps should always be updated to the latest version because this will ensure they are properly supported. Limit the amount of data that you allow these apps to use, including your photos and contacts, and other personal details.

Before trusting any app you come across in an online store, do your due diligence. This includes performing sufficient background research. Also, before downloading any app, check first the level of access requested and see whether this degree of exposure is actually warranted. Is it relevant to the use of the app and how it operates?

For instance, if you are about to download a photo-resizing app that is asking for access to your contacts, emails, text messages, and other personal details, this would be questionable, since the information is not relevant to the functioning of the app.

The challenge here is that you do not know how many other persons will be accessing this data, much less what they will do with it. Identity thieves typically use and then sell the data from victims to criminals in the dark web and this is the last thing you would want to happen to you.

2. Secure Your Ecosystem

Your other devices, including your laptop, desktop computer, and tablet will likewise need to be kept secure especially if they are connected, synced or share information with each other in other ways. The security measures discussed in this article should also be extended to the other devices that you own if they are sharing information with your phone.

Companies like Apple have their devices set up for this type of interactivity. The relationship is quite profitable for the company because it keeps the consumers dependent on the bundle offered instead of purchasing or updating singular devices. It is also quite convenient for the end-user who can have data sharing across all the devices used.

However, in an ecosystem of connected devices, access to one device may be all a hacker needs to take over everything. In one reported case, a victim lost his entire digital life because a teenage hacker had gained access to his Amazon account and then used this to infiltrate his phone. Once the hacker seized control of the phone, he was able to then control all the other devices in the victim's ecosystem, delete the records he found there and completely lock out the victim.

Unknown devices logged onto your social media accounts indicate that your phone has been compromised and will need to be disconnected immediately. After this, the password of the affected account should be changed at once. To identify such devices, go to the account settings of specific apps like Facebook on your phone and check the devices that currently logged in.

3. Leverage Anti-Hacking Software

Apps like ZIPS can be downloaded and installed on your phone to scan your device for suspicious activities and malicious software. Incognito is a free app that will scan your mobile for known malware, spyware, or other malevolent programs and create a security status report.

Such apps will also warn you if the network you are using is unsafe. In case you unwittingly click on a link and download a malicious program on your device, they alert you to the threat and you will be able to remove it from your device. If you are in a shared network, the apps are able to create a report and send it to the central command unit so that other users of the network are protected as well.

Another advantage of such apps is that they are able to identify trojans which typically stay hidden in the background for a long time and only activate in predetermined conditions. Having a powerful, reliable antivirus program will secure your phone from threats so ensure that you use an updated phone version, instead of one whose support has expired.

Periodically check your antivirus for any new threats or reports and be able to delete any malicious software. Bear in mind that sophisticated attacks that cannot be removed through antivirus programs or factory resets will require you to purchase a new phone.

In one reported case, a victim lost his entire digital life because a teenage hacker had gained access to his Amazon account and then used this to infiltrate his phone. Once the hacker seized control of the phone, he was able to move on to all the other devices in the victim's ecosystem, lock them and delete the records he found there.

4. Avoid Unsecured Networks

Free open wi-fi can be quite convenient, but this also carries a high risk of your device being accessed by unknown persons. Avoid connecting to networks that are unsecured or whose authenticity cannot be confirmed.

Instead of allowing the phone to automatically connect to wi-fi networks, you should select the option of doing it manually. This will prevent the device from exposure to risk without your knowledge when you come into the network range.

Avoid performing any sensitive online operations like financial transactions when you are not connected to your own private network. If you want to share your personal wi-fi connection with others, ensure that this is done in a private setting and not in public spaces.

5. Perform Security Tests

There are tests you can execute to check whether your phone is compromised. One way is by sending a text message to your phone number. After receiving the message, check the source.

If it does not correspond to your number or does not have your service provider details, there could be an interface capturing and screening all communication from your phone. Such interfaces are responsible for capturing and rerouting messages and other information from your phone to the hacker.

There are three USSD codes that you could use to check whether there is any suspicious activity involving your phone:

  • *#121# - confirms whether your outgoing calls are being diverted or rerouted elsewhere.
  • *#62# - returns a list of numbers that are receiving your voice or text messages and other redirected data.
  • ##002# - undoes redirection commands automatically if your voice or text messages and other data have been rerouted.

5. Reset Your Device

You could also perform a complete factory reset to restore your phone back to its original settings. Before doing the reset, however, ensure that you have all your data backed up elsewhere (including your photos, videos, and documents), since they will be irretrievably erased from your phone.

If you find the phone functionalities are too compromised and the level of infiltration on the phone cannot be rolled back by a factory reset (i.e. it is not enough to undo the damage) you may need to dismantle your phone and purchase a new one.

6. Charge Responsibly

Avoid charging your phone in public spaces that seem suspicious or unsecured. You may be exposing your mobile device to unscrupulous persons whose agenda is nothing short of identity theft and data transfer. If you are charging your phone away from home, select the 'Charging Only' option to ensure that data is not being siphoned away by third parties.

7. Be Cautious with Links

Clicking on unknown links or downloading unverified programs on your phone increases the risk level. One rule of thumb is that you should never try to access any links unless you are able to view the complete URL and ascertain that the site is legitimate.

8. Use Strong Passwords

Keep strong passwords and ensure you do not use the same passwords for all your accounts. Be prepared to change your passwords frequently and whenever you detect suspicious activity on your mobile device.

9. Safeguard Your Accounts

If you are not in your private network, log out of all your accounts once you have finished using them. It may be convenient for you to remain logged in for ease of access, but this also means that potential hackers can do the same and stay connected with all the details they need concerning you.

10. Investigate the IP Address

If you are using Android, you can find your IP address in Settings under About Device. Click on Status. Copy the IP address you find there to a resource like Linux or simply use a WHOIS IP address look-up tool like Ultratools.com. You can also check the source behind the address on WhatismyIP.com. Again, if the details you find are unrelated to your service provider, this is a sign that your phone could be compromised.

10. Be On Your Guard

Stay alert about what is going on and take precautions. Certain acts as simple as giving a stranger your phone to use in an 'emergency' can result in the phone being manipulated to start communicating with and sending information to the hacker. Make a habit of monitoring the incoming and outgoing communication from your phone with the readiness to act quickly in case of any unusual activities. Also, keep the amount of shared information to the minimum and ensure your phone is always locked when not in use.

11. Seek Professional Services

Taking your phone to a technician who is qualified and reliable is important because they will be able to do a thorough assessment of the device and investigate the source of problems, i.e. whether it has been hacked or there has been a technical glitch.

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