Our mobile devices are the gateway to our digital lives. The price we pay for this convenience is that it makes our devices an attractive target for malicious actors.
Our mobile devices are the gateway to our digital lives. At the tap of a screen, they provide access to everything from our online banking to messaging, photos, cloud storage and potentially sensitive workplace applications. The price we pay for this convenience is that it makes our devices attractive targets for malicious actors.
One of their favorite tools for peering into our digital lives is mobile spyware. So, let’s take a look at what it is, how it works and how to protect yourself.
What is mobile spyware?
Mobile spyware does what it says. It’s any malware designed to covertly steal sensitive information from your mobile device and/or monitor and track usage and location. What we’re talking about aren’t legitimate mobile monitoring tools of the sort used for parental controls or business mobile device management (MDM). Mobile spyware is deliberately, maliciously and secretly installed by cybercriminals, nation state operatives, stalkers and potentially even people we know personally.
Types of mobile spyware
Mobile spyware can have various functions. Some of the most common are:
- Keyloggers: Capture keystrokes, and in so doing allow adversaries to harvest passwords, credit card numbers and other sensitive information
- Location Trackers: Monitor GPS data to track your movements
- Call and SMS Monitors: Record your calls and text messages
- Multimedia Recorders: Can activate your device’s camera or microphone to capture images, videos and audio, including the content of private conversations and meetings
- Comprehensive Surveillance Apps: Typically combine many of the above features, such as logging keystrokes, tracking location and recording communications
How mobile spyware works
Infection vectors
Cybercriminals employ several methods to install spyware on your device:
- Phishing: Malicious actors attempt to steal users’ credentials or other valuable info via malicious content delivered in messages, links and communications, including emails encouraging you to click on links that covertly download the malware
- Malicious App Stores and Sideloading: Spyware disguised as legitimate-looking apps. These can sometimes end up in Google Play and the Apple App Store. Also common are attempts to sideloaded apps outside official markets. iPhone users may resort to jailbreaking or rooting their devices in order to access unsanctioned apps. This can compromise the security state of their devices in their bid to acquire tech from less-secure third-party app stores
- Malicious Advertising: Clicking on a malicious ad could trigger a spyware download
- Drive-by Downloads: Visiting a compromised website could trigger a malware download, even if you don’t interact with the site
- Rogue Wi-Fi: Beware of fake hotspots that attract users in order to install malware on their devices
- Vulnerability exploitation: Attackers may exploit security flaws in your operating system (OS) or legitimate applications to install spyware without your consent
- Physical Access: If someone gains temporary physical access to your device, they may alter or abuse existing functions in legitimate apps, such as built-in parental control, which offers features like device tracking and accessible call logs
How it operates
There are many types of mobile spyware circulating in the wild, but most will conform to the same operational characteristics:
- Stealth: It is designed to operate secretly without you knowing, perhaps by disguising itself as a legitimate app or coming bundled with harmless-looking software
- Installation: It can be installed remotely via links, malicious ads and websites, or app downloads. If a bad actor has physical access to your device, they may install it directly
- Data Collection: Once installed, spyware may include features that silently log keystrokes, capture your location, record calls and messages, and even take periodic snapshots of your screen amongst many other documented capabilities
- Data Transmission: Once collected, data is usually sent to remote servers, often via encrypted tunnels, which help it evade detection by security tools
Advanced features
Some spyware is more advanced than others. Sophisticated strains might adapt their behavior to avoid detection, such as disabling themselves when security software activates. Or it might enable an attacker to remotely switch on the mic/camera without triggering LED indicators. A particularly advanced category of spyware is installed on devices via zero-click attacks, which exploit unknown (zero-day) vulnerabilities and require no user interaction.
The risks and impact of mobile spyware
Both personal and corporate device users are at risk from mobile spyware. Here’s what’s at stake:
Personal risks
- Unauthorized Data Access: Spyware can expose sensitive personal details, including contacts, messages, browsing history and call content to malicious third parties
- Identity Theft: Stolen personal data may end up in the hands of scammers who will use it in identity fraud
- Financial Risks: Compromised banking or payment credentials could be used to hijack accounts and perform other unauthorized actions
Personal safety
Stalkerware, a sub-variant of spyware, can be installed on mobile devices by ex-partners, jealous spouses or stalkers to track the victim’s movements and conversations. This could potentially put them in physical danger. According to one report, the risk of encountering stalkerware on a mobile device increased 239% globally between 2020 and 2023.
Corporate risks
For businesses, the risk of mobile spyware is elevated by the large number of employee-owned devices allowed to access corporate networks and resources (known as BYOD). Infection could lead to:
- Data Breaches: Exposure of confidential information, trade secrets, and highly regulated personal information on customers and employees. Data may also be held for ransom by cyber criminals
- Corporate Espionage: Spyware could enable industrial espionage, damaging a company’s competitive edge
- Reputational Damage: A ransomware attack or data breach enabled by spyware may tarnish a brand in the eyes of customers, shareholders, partners and others
- Regulatory and Compliance Risk: Major breach incidents may invite the scrutiny of regulators, and lead to serious fines
Detection and diagnosis
If you’re concerned that your mobile device may be infected with spyware, consider the following:
Signs of spyware infection
- Unexplained Battery Drain: Spyware operating in the background can rapidly run down your battery
- Increased Data Usage: Sudden spikes in data consumption may indicate that spyware is transmitting information
- Device Slowdowns: If your phone becomes sluggish or unresponsive, or even crashes suddenly, it might be due to malicious processes consuming resources
- Unexpected Behavior: Look and listen out for unusual noises during calls, unfamiliar apps on the home screen, settings changes, or the mic/camera switching on at unusual times
How to detect spyware
- Mobile Security Apps: Anti-malware or anti-spyware solutions from reputable providers will scan your device for malware. They also come with other handy features such as payment protection, anti-phishing or anti-theft, and provide complex protection against viruses, ransomware and other malware
- Manual Inspection: Review your apps and permissions periodically and remove anything that looks suspicious
- Network Analysis: Keep an eye on your phone’s network activity. Unusual outbound traffic may be a sign that spyware is sending data to remote servers
OS security features
Mobile operating systems have various built-in security features designed to mitigate spyware risks, such as sandboxing, lockdown mode, strict app permission controls, full disk encryption and regular security updates. But not all spyware is created equal, and more sophisticated strains may be able to bypass some or all of these defenses. That’s why it pays to stay vigilant and take additional security measures.
Prevention and protection strategies
Get back on the front foot against mobile spyware by following these best practices:
Best practices for users
- Download from Trusted Sources: Only install apps from official app stores like Google Play or the Apple App Store
- Regular Updates: Ensure the device OS and any apps are on the latest and most secure versions
- Review App Permissions: Regularly check which apps have access to sensitive data and disable unnecessary permissions
- Use Strong Authentication: Enable multi-factor authentication (MFA) on all of your accounts to mitigate the risk of password theft
- Think Before You Click: Be vigilant when opening new messages, emails or chats, and avoid clicking any unknown or suspicious links
Advanced security measures
- Invest in Mobile Security Solutions: Choose anti-malware or anti-spyware from a trusted vendor. It should offer real-time monitoring to detect and block spyware before it can be installed
- To maximize its effectiveness:
- Run an initial device scan to check for any hidden spyware or malicious apps that may already be present on your phone.
- Enable Anti-Phishing protection including features like Notification Protection and Link Scanner to block phishing attempts and malicious links that could lead to spyware infections.
- Use the Security Audit feature to review your device’s app permissions and settings to identify potential vulnerabilities and ensure apps aren’t accessing more data than necessary.
Controls for organizations
- Mobile Device Management (MDM): Corporate IT departments should enforce strict security policies on employee devices using MDM tools. These can ensure devices are regularly updated and securely configured, app downloads are restricted, and so on
- Mobile Threat Defense (MTD): An MDM solution can also ensure MTD is maintained on end user devices to prevent suspicious downloads and scan for spyware
- User Education: Regular training on mobile security best practices can help employees recognize and avoid spyware threats
- VPN: Use a corporate VPN. This keeps users inside the company perimeter and lets employees access company resources from remote places in an authenticated and safe manner, giving a higher degree of control to the company IT/internal security
- Zero Trust: Consider adopting a zero-trust approach, which will deny access to spyware-infected devices
Legal and regulatory considerations
Spyware is primarily a security risk. But it can also create legal and regulatory challenges for organizations. Consider the following:
Legal frameworks
- Laws Against Unauthorized Surveillance: Many jurisdictions have strict laws against unauthorized installation and use of spyware. These include the GDPR in Europe, and the Computer Fraud and Abuse Act and various state-level privacy laws in the U.S.
So-called “commercial spyware” often operates in a regulatory grey area, as many of its vendors claim to only sell it for legitimate law enforcement purposes. However, former U.S. President Joe Biden took steps to ban it in 2023, and WhatsApp won a high-profile legal case in 2024 against one spyware vendor - Penalties and Responsibilities: Organizations found to be responsible for selling or installing spyware could find themselves facing major legal scrutiny and regulatory penalties. Equally, those deemed negligent in allowing spyware to steal protected customer/employee data could also face heavy fines, legal action and bad publicity
Compliance and best practices
- Data Protection Regulations: Companies must ensure their security practices comply with relevant data protection laws
- Regular Audits: Organizations should also perform security assessments to identify vulnerabilities and misconfigurations before they can be exploited
Future trends and evolving threats
Both attackers and defenders are innovating at pace as we enter a new era of mobile threats.
Emerging mobile spyware trends
- AI-Driven Spyware: Going forward, spyware developers may leverage artificial intelligence to improve the malware’s ability to adapt its behavior on the fly, evade detection and prioritize data collection
- Integration with Other Threats: Spyware could be combined with other threats to amplify their impact. For example, spyware could harvest voice recordings and other biometric data from a target to fuel deepfake fraud
- Malware-as-a-Service: Readymade service-based spyware offerings could lower the barrier to entry for budding cybercriminals
- Commercial Spyware Continues: Zero-click infections to deploy commercial spyware may grow in number as they are increasingly commoditized
New countermeasures
Fortunately, the cybersecurity industry is hitting back with innovations of its own, such as:
- Machine Learning and Behavioral Analytics: Advanced algorithms can detect abnormal behavior indicative of spyware
- Enhanced Operating System (OS) Security: OS developers continue to improve the mechanisms built into devices to protect against sophisticated spyware attacks. These include Lockdown Mode (iOS) to guard against zero-click threats, and Android Private Compute Core, which sandboxes sensitive processes
What the experts think
However, this is no time to let your guard down. As the arms race between attackers and defenders enters the AI age, the stakes will be raised yet again. The key is to remain vigilant and ensure you are using the latest tools, techniques and best practices available to combat spyware risks.
“Spyware is evolving from a niche hacker tool into a common threat that targets everyday users through apps that appear trustworthy. We’ve seen a surge in these attacks, including ’spyloan‘ apps that steal data, demand payments and extort their victims, or Trojanized chat and screen‑recording apps that can grab WhatsApp backups and other sensitive files. Attackers are adapting fast to slip past security measures, and some of these apps have even been found on official app markets.“Looking ahead, the lines between cutting-edge and commodity-driven attacks are likely to blur further, making advanced threats more of a standard in the black-hat market. They will also likely leverage AI to automate harvesting of data and refine stealth techniques, while also branching out into multi-device compromise — attacking victims' smartphones, wearables and even IoT hardware. Users should keep themselves informed, pay close attention to what permissions apps ask for, read reviews carefully and consider using reputable security tools to protect their devices. Collaboration between researchers, app stores and law enforcement will also be critical to contain this growing problem.”
- Lukáš Štefanko, ESET Malware Researcher
Conclusion: Spyware protection starts here
Mobile spyware is a threat to personal and corporate data. It can erode your privacy and personal finances, and poses a significant reputational, regulatory and financial risk to organizations. But understanding how it works is the first step to mitigating those risks. By shining a light on this shadowy threat, we can hit back at those who would do us harm.
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Frequently asked questions
Can you tell if spyware is on your phone?
You can tell if spyware is on your phone by looking for signs like unusual battery drain, increased data usage and unfamiliar apps. Random camera or microphone activation can also indicate spyware.
Can I tell if my phone is being monitored?
Yes, you can. Check for signs like overheating, odd noises during calls and rapid battery depletion. Unusual phone activity when not in use and performance issues are also indicators.
Can someone track my phone without my knowledge?
Your phone can be tracked without you knowing it using hidden software or GPS data exploitation. These methods can transmit your location and other sensitive information in real time.
Is spyware on a phone illegal?
Installing spyware on a phone without the owner’s consent is illegal and violates privacy laws.
What should you do after discovering spyware on your phone?
Disconnect the device from the internet and run a complete scan using reputable antimalware software. Reset your passwords, review your activity on social media accounts, and contact banks and authorities if you entered credit card details or log-in details for a website with access to your cards.
