What to Dial to See if Your Phone Is Hacked

Chris Thompson

By Chris Thompson


In today’s digitally connected world, our smartphones hold a treasure trove of sensitive information—from personal conversations and photos to financial data and online accounts.

Unfortunately, this makes them a prime target for hackers seeking to exploit our vulnerabilities. Phone hacking can have serious consequences, including identity theft, financial losses, and even personal safety risks.

While you might think there should be a single number you can call to instantly know if your phone is hacked, the reality is more complex.

Simple phone number checks won’t offer conclusive proof. However, there are specialized codes known as USSD (Unstructured Supplementary Service Data) codes, which can reveal clues about potential compromises.

These codes allow you to query your phone’s settings and potentially uncover signs of tampering or unauthorized activity.

In this article, we’ll dive into the specific USSD codes that can help you spot suspicious activity and explore what other signs to look out for.

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What Are USSD Codes?

Think of USSD codes as your phone’s secret language.

These shortcodes, typically starting with *# and ending with #, are quick commands you can use to communicate directly with your mobile network provider.

You’re probably familiar with some common uses of USSD codes, like checking your data usage or airtime balance.

But here’s the thing: USSD codes can also reveal clues about unusual activity on your phone — the kind that might be caused by a hacker.

While these codes don’t provide a definitive diagnosis, they offer a window into potential security issues. Think of them as warning lights on your dashboard; they might alert you to a problem, but further investigation is required to confirm if your phone has truly been hacked.

How to use USSD codes

  1. Open your phone’s dialer app.
  2. Enter the code exactly as shown in the sections below.
  3. Press the call button.
  4. Information will appear as a pop-up message on your screen.

ℹ️ The appearance and exact output of these codes may have slight variations depending on your service provider and phone model.

Fig 1: USSD code example – Checking call forwarding.

Common USSD Codes to Check for Phone Hacking

Call forwarding

Call forwarding lets you redirect incoming calls to a different phone number.

Hackers use this sneaky tactic to intercept your calls and gain access to verification codes sent by text or voice call.

Here are the USSD codes related to your call-forwarding settings:

➡️ *#21# – Check call forwarding status

Function: This code checks if any type of call forwarding is active on your phone and if so, it will display the number where your calls are being diverted.


  • To verify whether someone has maliciously activated call forwarding without your knowledge.
  • To check your own call forwarding setup (in case you activated it previously and forgot).

➡️ *#62# – Check forwarding when out of reach

Function: Specifically checks if calls are being diverted when your phone is out of service (no signal or switched off). It will display the number if it’s active.

Uses: Hackers might use this setting to intercept calls even when your phone is off or in a bad signal area.

➡️ *#61# – Check forwarding when you don’t answer

Function: Checks if calls are forwarded to another number when you don’t answer them after a certain number of rings. It will display the number if it’s set up.

Uses: Scammers can use conditional call forwarding to redirect your calls and verification texts to another mobile phone.

➡️ ##002# – Deactivate all call forwarding

Function: This is the quickest way to turn off all types of call forwarding settings at once. It’s a “reset” code.


  • If you suspect calls are being diverted unexpectedly.
  • After you’ve set temporary call forwarding and want to return to normal.

IMEI check

USSD code *#06# shows your phone’s unique IMEI (International Mobile Equipment Identity). The IMEI is like your phone’s fingerprint — a 15-digit number that identifies your specific device.

If your phone is stolen, knowing your IMEI is crucial. You can report the IMEI to your network provider and potentially have the device blocked from accessing their network, making it less valuable to the thief.

Other potentially helpful codes

➡️ *#4636## or *#197328640## – Hidden settings and diagnostics

These codes access a hidden menu in most Android phones. This menu contains various technical details and settings, including:

  • Phone information: IMEI, signal strength, etc.
  • Battery Information: Usage history, health information.
  • Usage statistics: Data about app usage times.
  • Wi-Fi Information: Network status, configurations, etc.

While NOT a direct malware detector, these codes can help you by providing:

✅ App list under usage statistics: See if there are unfamiliar or suspicious apps running in the background and consuming resources.

✅ Battery usage breakdown: If unknown apps are draining your battery excessively, it could point to malware running in the background.

⚠️ It’s important to note that this menu is meant for knowledgeable users. Exercise caution when changing settings. Also, this menu’s specific options and layout might vary slightly across Android phones.

➡️ *#232338## – View Wi-Fi MAC address

This code displays your device’s unique MAC (Media Access Control) address for its Wi-Fi hardware.

This code helps with:

✅ Network analysis: If you manage your router, you can compare the MAC addresses of the devices allowed on your Wi-Fi network to the MAC address on your cell phone.

✅ Suspicious connections: If an unknown device with a similar MAC address shows up, someone might try to “spoof” your device to intercept data.

💡 Expert Insight

"While USSD codes can provide some useful indicators of potential phone compromise, it's important to note that there is no number you can dial that will conclusively reveal if a phone is hacked. Hackers are sophisticated and often employ multiple tactics. Think of USSD codes as one tool in your toolbox, but not a complete solution for detecting advanced threats."

–Russell Kent-Payne, Co-founder of Certo

Other Indicators of a Hacked Phone

Beyond USSD codes, your phone often provides tell-tale signs if it has been compromised. Here are some common red flags to watch out for:

⚠️ Unusual battery drain: Malware and spyware lurking in the background can constantly strain your phone’s battery. If you notice it draining much faster than usual, even with light usage, investigate further.

⚠️ Poor performance: Has your iPhone or Android phone become sluggish? Hacking software can hog your device’s processing power, making apps lag, websites load slowly, or causing crashes.

⚠️ Unrecognized apps: Spotting unfamiliar apps you didn’t download yourself is a major warning sign. Hackers often disguise malicious software as seemingly harmless tools or games to hide on your device.

⚠️ Suspicious activity: Receiving strange texts from unknown numbers, seeing a flood of unwanted pop-ups, or noticing unexplained spikes in data usage could all suggest someone has unauthorized access to your phone.

ℹ️ While these signs are good indicators, they might also occur due to other factors like outdated software or hardware issues. However, combined with the results of your USSD code checks, they form a more reliable picture of your phone’s security.

🛡️ Certo Case Study

In January 2024, Alex, a Certo AntiSpy user, noticed odd behaviors on his iPhone, such as unexplained data usage and trouble receiving calls. He decided to investigate using the USSD code *#21#. To his surprise, he found that his calls were being forwarded to an unrecognized number — a clear sign of a security breach.

Seeking to understand the extent of the intrusion, Alex used Certo's app to scan his device. Certo quickly uncovered a hidden spy app, confirming his suspicions of being monitored.

However, further analysis revealed that this spy app was not responsible for the call forwarding. This indicated a more complex attack on Alex's phone, involving multiple methods of intrusion.

Armed with this knowledge, Alex was able to take comprehensive steps to secure his device, guided by Certo's support team. Removing the spy app and rectifying the unauthorized call forwarding was just the beginning. We also helped Alex implement additional security measures to protect against future threats.

Alex's case highlights how USSD codes alerted him to a problem but didn't provide the full picture of the compromise. Hackers often use multiple methods, requiring in-depth scanning tools to fully uncover.

What to Do If You Suspect Your Phone Is Hacked

If you find yourself in a situation like Alex’s, and the USSD codes or other signs point towards the possibility of your phone being hacked, taking swift action is crucial:

➡️ Change passwords: Immediately reset passwords for all sensitive accounts. This includes email, banking, social media, and other accounts holding important personal or financial data. Use unique, strong passwords for each account.

➡️ System updates: Keep your phone’s operating system and apps updated with the latest security patches.

➡️ Download with care: Stick to downloading apps from official app stores (the Apple App Store or Google Play Store) and research apps before installing them.

➡️ Avoid clicking strange links: Never click on links in texts or emails from unknown senders. These can lead to malware or phishing scams.

➡️ Factory reset: In persistent or severe cases, a factory reset might be necessary. This erases all data and returns your phone to its original factory settings. Before doing this, back up any essential data you want to preserve.

➡️ Run security scan: Install a trusted antivirus/anti-malware app on your phone (if you don’t have one already). Run a full scan to detect and remove any malicious software a hacker may have slipped onto your device.

Beyond USSD codes: Comprehensive threat detection with Certo

While USSD codes can offer valuable clues, they only scratch the surface when it comes to cybersecurity.

For robust defense against phone hacking, consider dedicated security apps like Certo. Our mobile security solutions offer advantages like:

✅ Deeper scans: Go beyond simple settings checks and thoroughly examine your device for a wide array of malware, spyware, keyloggers and other threats that could be hidden from basic tools – regardless of whether you have an iPhone or Android device.

✅ Protect WiFi: Helps you stay safe online by analyzing your current network for signs of unauthorized monitoring, router vulnerabilities and other threats.

✅ Tailored for your OS: Our apps are designed specifically for the unique security needs of Android and iOS, ensuring you get the best protection for your particular device.

Certo Mobile Security for Android

Fig 2. Securing a phone with Certo Mobile Security for Android.

Final Thoughts

Protecting your phone from hacking requires a multi-faceted approach.

While no single method guarantees complete security, a combination of tools and vigilance offers the strongest defense.

USSD codes provide initial clues, but being aware of common red flags like strange device behavior is equally important.

Consider using a dedicated security app like Certo for peace of mind and the best chance of detecting even sophisticated compromises.