Seven Ways Mobile Devices can be Hacked
You rely on your phone. Here are a few tips to keep it safe.
Mobile security often is tighter than PC security. When the mobile device revolution started, smart phone devices were purported to be locked down and immune to malware, unlike buggy PCs and vulnerable servers. Due to this locked down nature, most user users have a very high trust in their mobile devices. But mobile device users can still be fooled by social engineering techniques, and smartphones can still be hacked.
Method One: Zero-click spyware
The scariest and most sophisticated attacks on smartphones are zero-click attacks. These attacks do not require any direct user action to succeed. Zero click spyware are essentially found and/or created by groups known as private sector offensive actors (PSOAs) or commercial surveillance vendors (CSVs). Examples of these groups would be NSO Group and Candiru and they sell the exploits that they deliver to the highest bidder once they have been found.
With these types of exploits, the victim does not have to do anything out of the ordinary for the exploit to launch and this is why they are so dangerous. Because of this, these types of attacks have nearly a 100% success rate. In 2023, malicious cyber actors exploited more zero-day vulnerabilities to compromise enterprise networks compared to 2022, allowing them to conduct cyber operations against higher-priority targets," CISA wrote in a recently published advisory.
So how do these attacks work? First the vulnerability needs to be identified. The vulnerability can exist in either a messaging application (e.g., iMessage, WhatsApp), email protocols, web browsers, or in the operating systems on the device. After this the attacker must craft a Malicious Payload to utilize the exploit. This is usually disguised as seemingly harmless data like a text message, image, or even a missed call. This is then delivered to the target through the vulnerable application or service. Upon receiving the payload, the vulnerable application processes the data, unknowingly triggering the exploit. No user interaction is required to do this. Now the attacker can inject and execute malicious code onto the device, effectively installing the spyware. This spyware can then perform a variety of malicious activities, including data exfiltration, location tracking, activating the microphone and camera for eavesdropping and intercepting calls and text messages.
These types of attacks are often sold for six- or seven-figure sums to commercial vendors or nation-states. Because of this, mobile device zero-click exploits pose a serious and ongoing threat to high-value targets, and much less so for the masses. Ordinary users face many types of lower-tech attacks — but in many cases they can be just as dangerous.
Method Two: Social engineering
The easiest way for any hacker to break into any device is for the user to open the door for them. Of course, making that happen is easier said than done, but it’s the goal of most social engineering attacks.
Smartphone operating systems generally have stricter security regimes than PCs or servers, with application code running in a sandboxed mode that prevents them from escalating privileges and taking over the device. But that much vaunted security model, in which mobile users need to take affirmative action for code to access protected areas of the phone’s operating system or storage, has a drawback: It results in an abundance of pop-up messages that many users simply tune out. This is known as security fatigue.
Nearly everyone has received the prompt ‘Do you want to allow this application access to your photos?’ And because of the way the user experience has conditioned the acceptance of most prompts as a gate to accessing functionality, most users will just allow the app access to whatever it is requesting.
Thanks to recent upgrades in the attack tools used by organized groups, a resurgence in social engineering attacks is happening. Many forms of phishing and social engineering are now supercharged by AI. This includes deepfakes, hyper-personalized email, and text scams that take advantage of identity data from previous breaches.
How to protect yourself from Social Engineering:
Continually keep yourself up to date with Security Awareness Training.
Enable Multi-Factor Authentication (MFA) on all sites and services with an authentication app or hardware token. Companies should use SSO with MFA to control and protect user identities.
Utilize Strong Passwords and Password Managers.
Always verify the legitimacy of any requests for sensitive information, even if they appear to come from trusted sources.
Ensure all devices are properly secured and up-to-date with the latest security patches.
Limit Publicly Available Information by minimizing the amount of personal information you share publicly.
Method Three: Malvertising
Malvertising is a type of cyberattack where malicious actors use online advertisements to spread malware, often through fake or compromised ads. These attacks can infect devices, steal personal information, or even lead to ransomware attacks. On mobile devices, attackers are exploiting a very traditional mechanism that was specifically developed for the mobile advertising ecosystem, whether in a browser or within an app.
So how do advertisements become malvertising? It involves embedding malicious code or links within legitimate advertisements. These advertisements are often on trusted websites or platforms. When a user clicks on the advertisement or interacts with the malicious content, malware can be downloaded and installed on their device. Examples would be fake software updates or drivers, redirecting users to malicious websites, or exploiting browser vulnerabilities to perform drive-by downloads.
Many believe that this type of attack has become far less effective due to advancements in browser sandboxing, stricter app store policies, and the general shift toward app-centric mobile use over traditional web browsing. Yet, statistics say otherwise. Recently Google reported that they blocked 5.1B harmful ads and suspended 39.2M advertiser accounts in 2024, so it is clear that the malvertising problem is far from ineffective.
How to protect yourself from malvertising:
Use strong security software.
Be wary of suspicious ads. Blocking advertisements has become a very common security practice.
Stay informed on common malvertising tactics and best practices for avoiding online threats.
Be cautious about clicking on ads in general. Many firewalls and web filters blocks advertisements as a security measure.
Ensure your software is up-to-date.
Method Four: Smishing
Smishing is a type of cyber-attack that uses text messages (SMS or other messaging platform) to deceive victims into revealing personal information or clicking on malicious links. It essentially combines elements of "SMS" and "phishing."
Depending on the goal or intention there are many ways that scammers use smishing. If the objective is to install malware onto a device, then a file is usually attached, accompanied by a message that tries to persuade the user to click and download it. If the objective is to lure individuals into revealing sensitive data like passwords or credit card numbers then the scammers will pose as trustworthy organizations or individuals.
Essentially the techniques used in smishing are tried-and-true and have been around a long time. To make things more difficult to filter hackers are funneling malicious links through trusted domains like Google (using the AMP and Google Sites vulnerabilities).
How to protect yourself from smishing:
Be cautious of unsolicited text messages from unknown senders.
Avoid clicking on suspicious links.
Take regular Security Awareness Training to become aware of common smishing tactics
Verify the legitimacy of a message by contacting the sender directly instead of replying to or clicking on a link in the text.
Enable Multi-Factor Authentication (MFA) on all sites and services with an authentication app or hardware token. Companies should use SSO with MFA to control and protect user identities.
Method Five: Fake apps
This is essentially a special social engineering tactic. It is essentially a way to convinces people to infect their phones with malware by giving them an app they think they want. The fake app is usually designed to look and function like its legitimate counterpart, but it will contain malicious code.
These fake apps pose a significant security risk since they can be used to steal data, install malware, or compromise user devices. These apps can be found in both official and unofficial app stores, making it crucial for users to be aware of how to identify and avoid them.
So how does one spot these fake apps? One way is to check the app’s name and developer. Look for misspelled words or unusual names that deviate from the original app's name. Look up the developer to see if they have other apps or a history of creating legitimate applications. Read the App’s description. Typically, fake apps often contain poor grammar, typos, or vague descriptions, but this is not always the case. Look at the app's review and rating. Legitimate apps typically have numerous reviews and positive ratings. Fake apps may have few reviews or many negative comments. The same goes for the download count. Popular apps usually have a high download count. If an app claiming to be a well-known app has a low download count, it could be fake. Often, legitimate apps only request permissions that are necessary for their functionality. Fake apps may request unnecessary permissions, such as access to your contacts or microphone, even if it's not relevant to the app's purpose.
Protecting yourself from fake apps:
Avoid downloading apps from unofficial or third-party sources. Only use the official app store.
Enable app store security features. Many app stores have features that can help identify and block malicious apps.
Keep your phone's operating system and apps updated. These updates often include security patches that address vulnerabilities that fake apps may exploit.
Be wary of suspicious links and emails and take regular Security Awareness Training.
Enable Multi-Factor Authentication (MFA) on all sites and services with an authentication app or hardware token. Companies should use SSO with MFA to control and protect user identities.
Install a reputable security applications. Security apps can help detect and block malicious apps and malware.
Method Six: Pretexting
Pretexting is a form of social engineering where an attacker uses a fabricated story or scenario to deceive a victim into revealing sensitive information or performing actions that compromise their security. It involves creating a false pretext, or reason, to gain the victim's trust and manipulate them into giving up valuable information or access.
In the case of mobile devices, the attacker convinces the phone carrier to transfer the victim’s phone number to a device they possess, in what’s known as a SIM swap. Once completed all calls, texts, and access codes (like the second-factor authentication codes your bank or financial providers send to your phone via SMS) now go to the attacker and not you.”
Protecting yourself from SIM swap pretexting:
Secure Your Mobile Account by setting up a strong, unique password and PIN with your mobile carrier. Also, enable SIM protection features offered by your carrier, such as Verizon's SIM Protection or T-Mobile's Port Out Protection.
Enhance Account Security by using strong, unique passwords for all your online accounts.
Enable Multi-Factor Authentication (MFA) on all sites and services with an authentication app or hardware token. Companies should use SSO with MFA to control and protect user identities. (Text based MFA is the weakest form of MFA.)
Limit Publicly Available Information by minimizing the amount of personal information you share publicly.
Take regular Security Awareness Training to become aware of SIM swapping and pretexting techniques.
Method Seven: Gaining physical access to your phone
One of the most obvious, but overlooked, ways to install malware on someone’s phone is to do it manually. Essentially by gaining physical access to their device. This is of particular importance in domestic violence or stalking scenarios, but it is used for corporate espionage as well.
When a malicious actor has physical access to a device, the risk landscape changes significantly. Tools like FlexiSPY, mSpy, or Xnspy can be installed quickly and run silently, capturing text messages, call logs, GPS location, and even activating microphones or cameras without user awareness. For corporate espionage, malicious configuration profiles (especially on iOS) or sideloaded APKs (on Android) can be deployed to reroute data, manipulate network traffic, or introduce persistent backdoors. There are also hardware-based threats such as malicious charging cables, keyloggers, or implanted devices that can exfiltrate data or inject malware. However, these tend to be less common.
Tips to prevent physical access to mobile devices:
Avoid leaving your phone on a table in a restaurant, in your car, or in public places.
Always store your phone securely when not in use, such as a locked drawer or bag.
Minimize Visibility of you phone in public. Avoid leaving it visible in a car or through a window.
How can I tell if my device has been hacked?
If you are worried that your phone has been hacked there are a few things that experts say can point to a hacked device:
Look at the apps that are install. Be wary if a phone has apps installed that you didn’t request.
If an app is installed that has simplistic features, it could be offering one useful function while secretly performing another that is malicious.
Beware of any apps that have permissions that aren’t absolutely required. For example, geolocation is not generally required except for maps.
If you notice that your device suddenly started using more data than normal or is regularly bumping up against your monthly data limit and you have not changed your online habits there could be a spy at work send data back home from your device.
If your smartphone begins rebooting for seemingly no reason, someone could have installed malware or spyware on your device.
Back in the day of analog phone lines, we were used to noise in the background like buzzing or other voices leaking onto our calls. However, today’s digital phone networks have all but eradicated such noises. If you are hearing other voices or unknown sounds, someone could be spying on your calls.
It is true that a device’s battery life will deteriorate over the years is simply part of having a smartphone. But, a sudden drop in battery life could mean spyware or malware is making your device work overtime, running processes in the background. The harder your phone must work, the shorter its battery life. You may experience this alongside increased data usage