CVE-2021-40377: SmarterTools SmarterMail

Medium severity, CVSS 5.4. EPSS: 0.5% chance of exploitation in the next 30 days.

SmarterTools SmarterMail 16.x before build 7866 has stored XSS. The application fails to sanitize email content, thus allowing one to inject HTML and/or JavaScript into a page that will then be processed and stored by the application.

Affected products

• SmarterTools SmarterMail: from 16.0.6345, before 16.3.7866 (fixed in 16.3.7866)

Published 2021-09-08. Last modified 2026-06-17.