> There is a total shutdown of the affected resource. The attacker can render
> the resource completely unavailable.
Quote from the CVSS specification
Vulnerabilities with this tag were given a CVSS rating as part of the
requirement to be included into the [National Vulnerability
Database](https://nvd.nist.gov/). You can learn more about what the individual
scores mean in the [CVSS specification
document](https://www.first.org/cvss/specification-document).