What Is a Computer Worm?

How Do Computer Worms Work?

Computer worms can be transferred through software vulnerabilities or attachments in phishing emails. The worm then duplicates itself and spreads to uninfected computers in a process that is automatic and invisible to the user. The goal of a computer worm is to remain active on an infected system for as long as possible and spread to as many other systems as possible.

Worms can modify and delete important files, introduce additional malware, or steal data directly. Hackers can use computer worms to gain control over your computer. In other cases, a worm’s purpose may be to make copies of itself over and over, taking up hard drive space and slowing down your system.

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How Computer Worms Spread

Like other types of malware, cybercriminals use several methods to infect your devices with computer worms. Understanding these common methods for how computer worms spread can help you avoid them.

• Phishing emails. Emails can often look legitimate and carry dangerous computer worms. Avoid clicking links, downloading attachments, or visiting websites from email addresses you don’t recognize.
• Shared networks. Computer worms can replicate across devices sharing the same network.
• Security holes. Some types of computer worms can break into your system by exploiting system vulnerabilities.
• File sharing. File sharing networks can carry malware, including computer worms. Only use secure file sharing that you can trust.
• External devices. USB sticks and external hard drives can carry computer worms. Don’t use external devices unless you’ve purchased them new or trust where they’ve come from.

The Difference Between a Computer Worm and a Virus

Although viruses and worms create similar damage, they’re not the same type of threat. Viruses must be activated by their host, while worms are stand-alone programs that replicate as soon as they breach a system. If you accidentally download a virus, it will remain dormant until activated.
Worms don’t require any activation to spread, making them an especially dangerous threat.

How to Tell if You Have a Computer Worm

Computer worms often work invisibly, making them hard to detect. If you think your computer may be infected, run a virus scan immediately. While scanning for viruses should show any worms on your device, it’s possible that the scan may miss it. Be proactive by keeping an eye on your hard drive space, monitoring your device’s speed and performance, and looking out for missing or new files. Computer worms typically use up free space on your computer and can slow down your systems. If your computer has been unusually slow or you’re running out of storage, a computer worm may be at fault.

How to Prevent Computer Worms

The steps to prevent computer worms are similar to preventing other types of malicious software. To help avoid computer worms and other malware, practice good cyber hygiene and learn more about potential threats. Software vulnerabilities can be exploited by computer worms, so make sure your operating system and computer applications are updated regularly. Software updates often include patches for security flaws that could be allow access to worms. Be cautious of unsolicited emails from unknown senders and only open attachments or links that you can trust. Security software should include anti-phishing technology and defense against viruses, ransomware, and other cybersecurity threats.

Computer worms can easily spread and wreak havoc on your devices but following cybersecurity best practices prevents avoidable damage. Detecting worms as soon as possible can help keep your information secure.