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Zero day

(also zero-day vulnerability)

Zero day definition

Zero day is a broad term that includes both vulnerabilities and exploits. A zero-day vulnerability is a flaw in software or hardware which is yet to be discovered by its developers. A zero-day exploit is when cybercriminals discover the vulnerability and abuse it for their own means.

Real zero day examples

  • In 2010, a powerful computer worm called Stuxnet started exploiting the previously unknown Windows zero-day vulnerabilities. The worm caused enormous damage to the nuclear program of Iran and later was modified to target other facilities such as power plants and gas pipes.
  • In 2014, criminals utilized a zero-day vulnerability to break into Sony’s network and steal data. They released incredibly sensitive information, like copies of upcoming movies, business deals, and Sony's top management emails.

Stopping zero-day attacks

  • Update your software.
  • Stay informed about potential flaws in your software through vulnerability databases and bug bounty programs.
  • Be wary of phishing scams.