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Zero-day

A security flaw that attackers exploit before the software maker has released a fix. Keeping software updated closes them as soon as patches arrive.

Related terms

  • Adware
  • Antivirus
  • Botnet
  • Brute-force attack
  • Cookie
  • Credential stuffing
Cactus

Free, bilingual security tools to help you spot scams and stay safe online.

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