Phone acting weird? 5 red flags that could point to hackers

Source: ZDNet

Apple / Elyse Betters Picaro / ZDNET

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Your mobile phone is a treasure trove of personal and confidential information. That’s why it’s a prime target for hackers who want to compromise or steal your data. Through malicious apps and websites, phishing attacks, and other threats, an attacker can gain control of your device via spyware. But how can you tell if your phone has been hacked or tapped?

Also: Half of all cyberattacks start in your browser: 10 essential tips for staying safe

Amy Clark, managing editor of consumer‑reviews site TechReport, has put together a helpful guide on phone‑hacking threats. The guide shares advice on how to tell if your phone may have been hacked and how to fight back against the hacker.

Warning Signs of a Phone Hack

1. Battery drains faster than usual
   Spyware runs continuously in the background, which can cause a noticeable drop in battery life. Check your battery usage stats for any apps that are consuming an unusually high amount of power.

2. Device feels sluggish
   If apps are crashing, freezing, or taking longer to open, it may be a sign that malicious software is taxing your phone’s resources. Monitor performance over time to spot any degradation.

3. Unfamiliar login attempts
   Many services send alerts when they detect logins from odd times or distant locations. Such notifications can indicate that someone has gained access to your device and is trying to use your credentials. Change the affected account passwords immediately.

4. Sudden loss of storage space
   Spyware often stores data locally before transmitting it, which can eat up storage without being visible in the app drawer. Compare your current storage usage with a previous baseline to see if there’s an unexplained increase.

5. Unknown apps installed
   An unfamiliar app may be a malicious component placed by a hacker. Review the full list of installed applications, research any you don’t recognize, and uninstall anything suspicious.

How to Combat a Hack

If you suspect your phone has been hacked or tapped, you can use USSD (Unstructured Supplementary Service Data) codes to check for and stop call forwarding. USSD codes are short numeric strings you enter on your phone’s keypad; many carriers provide them for balance checks, troubleshooting, and special features.

Why USSD Helps

• Certain USSD codes reveal whether your calls or SMS messages are being redirected—a common sign of a compromised device.
• Other codes can disable that redirection.

Also: What is a passkey? The easy explanation – and how they beat passwords

Types of Call Forwarding

How to Use a USSD Code

1. Open the Phone app.
2. Switch to the keypad.
3. Type the code exactly as shown (including *, #).
4. Press the Call button (if required).

Useful USSD Codes (Android & iOS)

Also: Why rebooting your phone daily is your best defense against zero‑click attacks

Manual Factory Reset (if needed)

A factory reset wipes all data and apps, removing most malware or spyware that might have been installed.

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