As immediate action, update the affected plugin. If you're unable to do so, ask your hosting provider or web developer for help.
Logged-in users can be tricked into performing actions they didn't intend, like changing passwords or making purchases.
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.
Patchstack has issued a mitigation rule to block any attacks until you have updated to a patched version.
Update to version 1.7.7 or later to resolve the vulnerability. Patchstack users can turn on auto-update for vulnerable plugins only.