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Worm

What is a computer worm?

Worms are malicious programs similar to viruses: they cause havoc on devices and are able to self-replicate.


What they are after

Unlike viruses, which need human action to propagate, worms are able to send out hundreds of thousands of copies of themselves via email, or spread via USB devices and shared folders.


Known cases

Some of the most high-profile cases of worms include:

  • ILOVEYOU, which spread via email and caused businesses over 5.5 billion dollars in damage
  • Stuxnet, which attacked Iranian nuclear centrifuges, and was spread via USB devices
  • SQL Slammer, which slowed down the Internet for a brief period of time by attacking Internet hosts
  • Blaster worm, which forced computers to repeatedly and automatically reboot

How to block worms

Our Antivirus software Avira Free Antivirus helps to pretect its users from worms. 

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Automatically renews, unless the renewal is cancelled. Subscription details below.*
Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Subscription details below.*
Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Price subject to change.
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Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Price subject to change.
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Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Price subject to change.
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Special offer until #cma_promo_end_date#: #cma_promo_price# — #cma_promo_saved_price# off the 1st #cma_period# price of #cma_promo_standard_price#. Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Price subject to change.
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Special offer for the 1st #cma_period# until #cma_promo_end_date#. Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Subscription details below.*
Special offer for the first #cma_period# until #cma_promo_end_date#. Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Subscription details below.*
Special offer for the 1st #cma_period# until #cma_promo_end_date#. Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Subscription details below.*
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Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Savings compared to the renewal price. Subscription details below.*
Special offer for the 1st #cma_period# until #cma_promo_end_date#. Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Subscription details below.*
Special offer for the first #cma_period# until #cma_promo_end_date#. Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Subscription details below.*
Special offer for the 1st #cma_period# until #cma_promo_end_date#. Automatically renews at #cma_promo_renewal_price# / #cma_renewal_period#, unless the renewal is cancelled. Subscription details below.*
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Payment method required. When trial ends: paid subscription starts and automatically renews, unless the renewal is cancelled. Price subject to change.
Offer details below.*
#cma_promo_price# — #cma_promo_saved_price# off the 1st #cma_period# price of #cma_promo_standard_price#. Then #cma_promo_renewal_price# / #cma_renewal_period#.
#cma_promo_price# — #cma_promo_saved_price# off the first 2 year price of #cma_promo_standard_price#. Then #cma_promo_renewal_price# / #cma_renewal_period#.
#cma_promo_price# — #cma_promo_saved_price# off the 1st #cma_period# price of #cma_promo_standard_price#. Then #cma_promo_renewal_price# / #cma_renewal_period#.
The remaining value left on your current subscription is converted into additional days in your new subscription.
Big savings. Strong online security: 60% off Avira Prime >
Riesen Rabatt. Starke Online-Sicherheit: 60 % auf Avira Prime >