SECURITY SERIES - PART 2 OF 5

Malware, Ransomware & Viruses: Understanding Digital Threats

What is Malware?

Malware (malicious software) is any program designed to harm your computer, steal information, or give criminals control of your system. Think of it as digital disease—just like biological viruses make you sick, computer malware makes your system sick.

The term "malware" is an umbrella that covers many types of malicious software, each with different goals and behaviors.

Types of Malware Explained

Deep Dive: Ransomware - The £2.3 Billion Threat

Ransomware has become the most financially damaging type of malware. Let's understand how it works and why it's so devastating.

How Ransomware Attacks Happen

What Ransomware Encrypts

• Documents (Word, Excel, PDF)
• Photos and videos
• Databases
• Email archives
• Design files (AutoCAD, Photoshop)
• Accounting software data
• Customer records
• Network drives and cloud-synced folders

Should You Pay the Ransom?

Law enforcement and security experts unanimously say: NO

Why not to pay:

• No guarantee you'll get files back – 40% of victims who pay never receive decryption keys
• You become a repeat target – Criminals know you'll pay and will target you again
• Funds criminal activity – Your payment finances more attacks
• Malware may remain – Even if you decrypt files, the infection might still be present
• Legal complications – In some cases, paying ransoms may be illegal (funding terrorism)

Real Ransomware Families in 2026

Ransomware Name	Typical Ransom	Target
LockBit 4.0	£50,000-£5 million	Large businesses, hospitals
ALPHV/BlackCat	£100,000-£10 million	Corporations, critical infrastructure
Ryuk	£50,000-£1 million	Healthcare, government
Cerber	£500-£5,000	Home users, small businesses
WannaCry (older)	£300	Unpatched Windows systems

How Malware Infects Your Computer

1. Email Attachments

2. Malicious Downloads

• Pirated software ("free" Photoshop, Windows, games)
• Fake system optimizers ("Speed up your PC!")
• Torrent files
• Codec packs for video players
• Browser toolbars and extensions

3. Drive-by Downloads

Simply visiting an infected website can trigger automatic downloads. This happens through:

• Malicious advertisements (malvertising)
• Compromised legitimate websites
• Exploit kits targeting browser vulnerabilities

4. USB Drives and External Media

Never plug in USB drives you find or receive unexpectedly. They can contain malware that auto-runs when connected.

5. Software Vulnerabilities

Outdated software has security holes that malware exploits:

• Old versions of Windows (XP, 7, 8)
• Outdated Java or Flash Player
• Unpatched browsers
• Old PDF readers

Warning Signs Your Computer Has Malware

• Sudden slowdown: Computer takes forever to start or programs lag
• Unexpected pop-ups: Ads appearing even when browser is closed
• Browser changes: Homepage changed, new toolbars appeared, search redirects
• Programs closing automatically: Especially antivirus software
• Files disappearing or corrupted: Documents won't open or show strange extensions
• Antivirus disabled: You can't turn it back on or it's uninstalled
• Unknown programs in startup: New programs you don't recognize
• High CPU or disk usage: Computer always running at 100%
• Webcam light on: When you're not using it
• Strange network activity: Internet usage when you're not browsing
• Friends reporting spam from you: Your email or social media sending messages without your knowledge
• Fake security warnings: Pop-ups claiming you have viruses (trying to sell fake antivirus)

How to Protect Yourself from Malware

• Install reputable antivirus software – Windows Defender (built-in) is good; BitDefender, Norton, or Kaspersky are better
• Keep ALL software updated – Windows Update, Adobe, Java, browsers—everything
• Never download pirated software – That "free" Photoshop is loaded with malware
• Be extremely careful with email attachments – Even from people you know (their account might be hacked)
• Use ad-blockers – uBlock Origin blocks malicious advertisements
• Enable click-to-play for plugins – Don't let Flash or Java run automatically
• Use a standard user account – Don't browse the internet as administrator
• Enable firewall – Both Windows Firewall and your router's firewall
• Disable macros in Office – Unless you absolutely need them
• Use Script Blockers – NoScript or uMatrix for advanced users
• Verify downloads – Only download software from official websites
• Check file extensions – document.pdf.exe is NOT a PDF file

The Backup Strategy: Your Best Defense Against Ransomware

The single most important protection against ransomware is having backups that malware can't access.

The 3-2-1 Backup Rule

Good Backup Strategy

1. External hard drive – Back up weekly, then DISCONNECT the drive (ransomware can encrypt connected drives)
2. Cloud backup – Services like Backblaze, Carbonite, or OneDrive with versioning enabled
3. Test your backups – Actually try restoring files to make sure backups work

What to Do If You're Infected

If You Suspect Malware (Not Ransomware)

1. Disconnect from internet immediately – Prevents malware from spreading or communicating
2. Don't restart – Some malware activates on restart
3. Boot into Safe Mode – Restart, press F8, select Safe Mode with Networking
4. Run antivirus scan – Full system scan in Safe Mode
5. Use second opinion scanner – Malwarebytes, HitmanPro (malware might have disabled your main antivirus)
6. Change passwords from clean device – After removing malware, change all passwords from phone or different computer
7. Monitor accounts – Watch for suspicious activity in email, banking, social media

If You're Hit by Ransomware

Mac Users: Are You Safe?

Mac-Specific Threats

• Adware – MacKeeper, Advanced Mac Cleaner (ironically, these "cleaners" ARE malware)
• Cryptominers – Using your Mac to mine cryptocurrency
• Spyware – Stealing iCloud credentials
• Ransomware – KeRanger, EvilQuest target Macs

Mac Protection

• Keep macOS updated – Apple releases security patches regularly
• Only install apps from App Store – Or verified developers
• Enable Gatekeeper – System Preferences > Security & Privacy
• Use antivirus – Malwarebytes for Mac, BitDefender, or Intego
• Don't disable security features – Even if an installer asks you to

Recommended Antivirus Software

Software	Best For	Price	Pros
Windows Defender	Basic protection	Free (built-in)	No extra cost, lightweight, good detection rates
BitDefender	Overall best	£24.99/year	Excellent protection, minimal system impact
Norton 360	Complete suite	£34.99/year	Includes VPN, password manager, cloud backup
Kaspersky	Advanced users	£29.99/year	Powerful features, excellent detection
Malwarebytes	Removal tool	£39.99/year	Excellent for cleaning infected systems

Action Plan: Protect Yourself This Week

Free Malware Removal Tools

• Malwarebytes Free – Excellent malware scanner and remover
• HitmanPro – 30-day free trial, second opinion scanner
• AdwCleaner – Removes adware and unwanted programs
• ESET Online Scanner – Free one-time scan
• Kaspersky Virus Removal Tool – Free standalone scanner
• No More Ransom – Free ransomware decryption tools (nomoreransom.org)

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About the Author: Sean Kevin Wyndham-Quin has over 20 years of experience in computer repair and security. At Mac & PC Farnham, he removes malware from dozens of computers every month and helps clients implement robust security measures.

Tags: malware, ransomware, computer virus, spyware, antivirus, computer security, malware removal Farnham, ransomware protection, cybersecurity, online safety