What is spyware and how to prevent it

One compromised device, and someone suddenly has eyes on your business. Spyware was behind 20% of successful malware attacks in late 2024, and it’s still growing. Find out what spyware is, how it gets access, the damage it can do, and how to prevent it.

What is spyware?

Spyware is a cyberattack that secretly monitors what you do – collecting everything from login details and financial records to confidential business messages – and sending it all back to the attacker to exploit or sell.

How does spyware work?

It doesn’t crash systems or lock you out. Spyware enters unnoticed, blends in, and steals as much information as possible, for as long as possible. On average, breaches linked to stolen credentials–often due to spyware–took almost 300 days to identify and contain.

Once inside, it typically:

1. Installs silently

It embeds itself without triggering obvious alerts. Some variants even disable your security tools to avoid detection.

2. Monitors your system

It tracks keyboard strokes, tracks browser history, captures screen content, and accesses files.

3. Captures sensitive data

That includes passwords, bank details, business documents, and customer info.

4. Sends data back

Everything is sent to an external server controlled by the attacker–ready to be sold, leaked, or used in further attacks.

What are the different types of spyware?

Spyware comes in different forms, each with its own tactics. Here are the most common ways they get in, and what they can do:

How spyware gets in:

• Trojans disguise themselves as trusted downloads, while installing spyware or allowing remote access.

• Mobile spyware hides in apps or links to track calls, messages, locations, and app use.

• Browser hijackers sneak in via toolbars, malicious extensions, or fake software updates.

What spyware does:

• Adware bombards users with unwanted ads that can slow devices and open the door to more serious malware.

• Infostealers harvest stored credentials, browser data, and even financial info.

• Keyloggers record every keyboard stroke, giving hackers a front row seat to your systems and operations in real time.

• Browser hijackers change settings or redirect users to fake websites to steal data or serve ads.

Impact of spyware on SMEs

Spyware can seriously disrupt any business, but for SMEs, the consequences can be especially damaging, including.

• Financial loss

As well as direct financial theft, costs can mount through downtime, system repairs, investigations, and regulatory fines.

• Data breaches

Stolen personal or sensitive data can trigger serious legal and regulatory action under GDPR or other country-specific privacy laws.

• Operational disruption

Slower systems, corrupted files, or software glitches can bring daily operations to a stop.

• Reputational damage

Clients and partners expect you to protect their data. A breach can destroy trust and jeopardise future business.

• Long-term exposure

Stolen plans, credentials, or intellectual property can weaken your competitive edge for years.

How do you tell if you have spyware?

The clearest giveaway is sudden changes in how your device behaves–especially when there’s no obvious reason.

You might notice:

• Slower performance

Booting up, switching between apps, or loading files takes longer. Spyware often drains system resources.

• Browser issues

Webpages look different, links behave strangely, or you're redirected to unfamiliar sites.

• Unwanted pop-ups

Excessive, persistent ads or warning messages–even when you're offline.

• New or unfamiliar programmes

New apps or software appear that no one remembers installing.

• Battery or data drain

Spyware runs constantly in the background, which can hammer battery life and spike network activity.

One or two of these issues might be harmless. But it’s always worth checking for hidden threats.

How can spyware be prevented?

It’s not all bad news—spyware prevention is a mix of smart habits and solid tech.

• Use high-quality anti-spyware tools

Choose antivirus or anti-malware with real-time scanning, behaviour monitoring, and automatic updates.

• Download from trusted sources

Stick to official app stores and verified platforms. Scan files before you open or install anything.

• Tighten your cookie settings

Not all cookies are harmless. Adjust your browser settings to reject third-party cookies or ask before accepting them.

• Secure your network

Use strong passwords, multifactor authentication, and encrypted Wi-Fi. For remote work, use a VPN.

• Team training

Human error is still a leading cause of breaches. Regular cybersecurity training helps people spot phishing attempts, avoid risky downloads, and report anything suspicious.

• Avoid unsecured Wi-Fi

Unsecured or free networks are prime spyware territory. Encourage your teams to use secure connections or VPNs when working on the go.

• Keep everything up to date

Spyware evolves fast. Patch vulnerabilities regularly with software and system updates.

Protect your business from security risks

Spyware plays the long game. It hides and feeds off routine. Spotting it means being proactive, staying alert, questioning the unusual, and building the right defences.

It’s also one of many cyberthreats. Check out our small business antivirus and malware guide or our ‘what is ransomware’ piece for more.

The sooner you act, the safer your business stays.

Looking for more about spyware or like to learn more about cybersecurity across the board? Our V-Hub Digital Advisers are here to help.