Worm - what it is, how it spreads, and simple steps to stop it

Worm

What it is

A worm is malware that spreads by itself over the internet or your Wi-Fi. It doesn’t need you to open a file. It finds weak spots on devices and jumps to them, then keeps spreading. Some worms steal data, some slow your PC, and some bring in more malware. Learn more: https://gridinsoft.com/worm

Why it matters

One infected device can quickly turn into many. That can mean stolen accounts, broken apps, and a slow or unusable network.

How it works 

  • Scan: looks for devices with bugs or easy passwords.

  • Exploit: breaks in using that weakness.

  • Copy: installs itself and starts scanning from the new device.

  • Payload: may steal data, mine crypto, or drop ransomware.

Red flags

  • Internet feels slow and your router lights are going wild.

  • Lots of failed logins in logs or new accounts you didn’t create.

  • Multiple devices show security alerts at the same time.

  • Apps or services crash across different PCs.

Do it right

  • Update everything: Windows, phones, apps, and your router firmware.

  • Lock Wi-Fi: use WPA2 or WPA3 with a long password.

  • Close doors: turn off unused remote access and UPnP on the router.

  • Run protection: keep real-time anti-malware on.

  • If hit: disconnect from the network, update and scan each device, change passwords from a clean device, and reboot your router after updating it.

    Glossary (A–Z)

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