zero-day

See also: zero day

English

Alternative forms

• zero day
• 0-day

Pronunciation

• Audio (General Australian):

  (file)

Adjective

zero-day (not comparable)

1. (computing) Of warez, released less than a day after the official product release.
   • 2020, Oliver Markus Malloy, Bad Choices Make Good Stories:

     Back then, having "zero day warez" (brand new cracked games that are not even one day old yet) on your BBS first was a big status symbol.

2. (computing) Of a vulnerability, newly discovered, and therefore still not fixed and possibly exploited by hackers or other criminals.
3. (computing) Of an exploit or its threat or an attack, benefiting from a newly found and yet unpatched or unmitigated flaw in software or hardware; using a zero-day vulnerability.
   • 2003, John Viega, Matt Messier, Secure Programming Cookbook for C and C++:

     If your software is popular and has a high demand, you will want to defend against the "zero-day" cracker.

   • 2014, Michael Gregg, CASP CompTIA Advanced Security Practitioner Study Guide: Exam CAS-002‎^[1]:

     Before discussing ways to counter zero-day attacks, let's begin with the definition of what a zero-day attack is. A zero-day attack is one that the vendor does not yet know about or hasn't been fixed.

   • 2005, Valdes et al, Recent Advances in Intrusion Detection

     Automatically creating reliable signatures of zero-day exploits is the focus of intense research efforts.

4. Used other than figuratively or idiomatically: see zero,‎ day.

   Average residues of 1.44 and 2.18 mg/kg chlortetracycline were seen in liver and kidney, respectively, at zero-day withdrawal.

Noun

zero-day (plural zero-days)

1. (computing, idiomatic) A vulnerability that has been discovered recently, and is yet unpatched or unmitigated; a zero-day vulnerability.

   New Internet Explorer zero-day exploited in Hong Kong attacks

   These days, however, more zero days are being used and discovered.

   All the four zero-days originally were reported to Microsoft, affecting Internet Explorer on the desktop.

References

• Hacker Lexicon: What Is a Zero Day? (on Wired.com)
• 0-day (zero-day) (on About.com)
• What is a Zero-Day Vulnerability? (on PCTools.com)

Anagrams

• zedoary