It was previously called a “zero-day exploit”. It referred to the time after a vulnerability was published for a corresponding exploit to appear. A zero-day exploit is one that appears together with the security vulnerability, leaving the software maintainer zero days to fix the vulnerability before anyone can exploit it.
Later people started to call security vulnerabilities for which a zero-day exploit exists “zero-day vulnerability” or just “zero day”.
It was previously called a “zero-day exploit”. It referred to the time after a vulnerability was published for a corresponding exploit to appear. A zero-day exploit is one that appears together with the security vulnerability, leaving the software maintainer zero days to fix the vulnerability before anyone can exploit it.
Later people started to call security vulnerabilities for which a zero-day exploit exists “zero-day vulnerability” or just “zero day”.