> For the complete documentation index, see [llms.txt](https://learn.sitecove.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://learn.sitecove.com/how-to-guides/website-security-and-maintenance/malware-and-threat-protection/common-types-of-malware.md). # Common Types of Malware #### What is Malware? Malware (malicious software) is any program or code designed to harm, exploit, or gain unauthorized access to a computer system or network. Cybercriminals use malware to **steal sensitive information, disrupt operations, and damage devices**. Understanding the different types of malware helps in implementing better security measures. *** #### Ransomware **What is Ransomware?** Ransomware is a type of malware that **encrypts a victim’s files** and demands a ransom payment in exchange for a decryption key. Without the key, victims lose access to their files, making ransomware a major threat to businesses and individuals. **How Ransomware Spreads** * **Phishing Emails** – Malicious email attachments or links. * **Exploit Kits** – Attacks on system vulnerabilities. * **Malicious Websites** – Drive-by downloads from compromised websites. * **Remote Desktop Protocol (RDP) Attacks** – Unauthorized access to remote systems. **Examples of Ransomware** * **WannaCry** – Global attack in 2017 affecting hospitals, businesses, and individuals. * **Ryuk** – Targeted attacks on organizations demanding large ransom payments. * **Locky** – Spread through email attachments disguised as invoices. **How to Protect Against Ransomware** * **Back up important files** regularly to an offline location. * **Do not open suspicious email attachments or links**. * **Keep software and operating systems updated** to patch vulnerabilities. * **Use advanced endpoint protection** with behavior-based detection. * **Disable Remote Desktop Protocol (RDP) if not needed**. *** #### Spyware **What is Spyware?** Spyware is malware designed to **secretly monitor user activity** and collect personal information such as passwords, browsing history, and financial data. It operates in the background without the user’s knowledge. **How Spyware Spreads** * **Free Software Downloads** – Bundled with legitimate applications. * **Malicious Websites** – Drive-by downloads that install spyware automatically. * **Phishing Emails** – Fake links that trick users into downloading spyware. * **Infected USB Devices** – Transferred through removable storage devices. **Examples of Spyware** * **Keyloggers** – Record keystrokes to capture passwords and personal data. * **Trojan Spyware** – Disguises itself as a legitimate program while spying on users. * **Pegasus** – Advanced spyware used to monitor government officials and activists. **How to Protect Against Spyware** * **Avoid downloading software from untrusted sources**. * **Use a reputable anti-spyware or anti-malware tool**. * **Enable browser security settings to block suspicious scripts**. * **Regularly scan devices for spyware infections**. *** #### Adware **What is Adware?** Adware is a type of malware that **displays unwanted advertisements** on a user’s device. While not always harmful, some adware can be intrusive, slow down performance, and redirect users to malicious sites. **How Adware Spreads** * **Bundled Software** – Hidden in free downloads and installed without user consent. * **Malicious Ads (Malvertising)** – Fake online advertisements leading to malware downloads. * **Browser Extensions** – Installed add-ons that inject ads into web pages. **Examples of Adware** * **Fireball** – Hijacks browsers and collects user data for ad revenue. * **Gator** – Displays pop-up ads and tracks user browsing habits. * **DollarRevenue** – Redirects users to unwanted advertising websites. **How to Protect Against Adware** * **Be cautious when downloading free software** and check for bundled applications. * **Use ad blockers to prevent intrusive ads and tracking**. * **Regularly clear browser cache and remove suspicious extensions**. * **Scan devices with anti-adware tools to remove infections**. *** #### Other Common Types of Malware **Trojans** * Disguised as legitimate software but performs malicious activities. * Commonly used to install backdoors or steal data. **Worms** * Self-replicating malware that spreads across networks without user interaction. * Causes widespread disruption and slows down systems. **Rootkits** * Grants attackers remote control over a system. * Hard to detect as they operate deep within system files. **Botnets** * Networks of infected computers controlled remotely. * Used for DDoS attacks, spam distribution, and data theft. *** #### Summary of Malware Types and Prevention Methods | Malware Type | Purpose | How It Spreads | Prevention Methods | | ------------ | ----------------------------------------------------------- | -------------------------------------------------------- | ----------------------------------------------------------- | | Ransomware | Encrypts files and demands ransom | Phishing emails, exploit kits, malicious downloads | Regular backups, patch vulnerabilities, disable RDP | | Spyware | Monitors activity and steals data | Free software, phishing, infected websites | Anti-spyware tools, safe browsing, security updates | | Adware | Displays unwanted ads and collects data | Bundled software, browser hijackers, malicious ads | Ad blockers, scan for malware, remove suspicious extensions | | Trojans | Disguised as legitimate software to perform malicious tasks | Infected downloads, fake software updates | Use reputable software, enable antivirus protection | | Worms | Self-replicates and spreads across networks | USB drives, email attachments, unpatched vulnerabilities | Regular software updates, disable autorun features | | Rootkits | Hides deep in system files to gain control | Malicious downloads, backdoor exploits | Rootkit detection tools, avoid downloading unknown programs | | Botnets | Turns infected computers into a network for cybercrime | Phishing, malware infections, compromised websites | Use a firewall, monitor network activity, scan for malware | Understanding different types of malware and their behaviors is key to preventing infections and protecting devices and networks from cyber threats. --- # Agent Instructions This documentation is published with GitBook. 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