WordPress · Fluentsmtp · CVE-2026-16636
**Name of the Vulnerable Software and Affected Versions**
FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider versions prior to 2.2.96
**Description**
Insufficient input sanitization and output escaping allow unauthenticated attackers to perform Stored Cross-Site Scripting (XSS), a technique where malicious scripts are permanently stored on the target server. The issue occurs in the Email Logs detail view when an administrator uses the Prev/Next navigation controls, as this specific path bypasses the `escapeHtml` pipeline. The malicious payload is delivered through the `to.name` variable within a `wp mail()` function call.
**Recommendations**
Update FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider to version 2.2.96 or later.