CVE-2026-16636 PUBLISHED

FluentSMTP <= 2.2.95 - Unauthenticated Stored Cross-Site Scripting via Recipient Display Name (to.name) in Email Logs

Assigner: Wordfence
Reserved: 22.07.2026 Published: 06.08.2026 Updated: 06.08.2026

The FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Recipient Display Name (to.name) in Email Logs in all versions up to, and including, 2.2.95 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The payload is delivered via an attacker-controlled recipient display name (to.name) in a wp_mail() call and does not fire in the log list view — only in the detail view when an administrator uses the Prev/Next navigation controls, as that path bypasses the escapeHtml pipeline used by the list view.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
CVSS Score: 7.2

Product Status

Vendor wpmanageninja
Product FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP
Versions Default: unaffected
  • affected from 0 to 2.2.95 (incl.)

Credits

  • Fraudless finder

References

Problem Types

  • CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE