This could allow a malicious actor to execute code injection, SQL injection, path traversal, denial of service, and more if a proper POP chain is present.
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 3.4.5 or later to remove the vulnerability. Patchstack users can turn on auto-update for vulnerable plugins only.