A denial of service attack occurs when a malicious actor can cause the endpoint, or website, to crash or refuse to serve requests to one or more users by causing it to hang, crash or make unusable.
CVSS score is a way to evaluate and rank reported vulnerabilities in a standardized and repeatable way but which is not ideal for WordPress.
This security issue has a low severity impact and is unlikely to be exploited.
Update to version 1.6 or later to remove the vulnerability. Patchstack users can turn on auto-update for vulnerable plugins only.