FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP vulnerabilities
Plugin slug fluent-smtp · 6 known vulnerabilities · latest disclosed 2026-08-05 · WordPress.org page
Every listed vulnerability has a fix. Version 2.3.0 or later is not affected by any of them. If your site runs an older version, update it.
3 of 6 rated high or critical (CVSS 7 or more).
Known vulnerabilities in FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP
| Severity | Affected versions | Fixed in | CVE | Published | Details |
|---|---|---|---|---|---|
| High 7.2 | <= 2.2.95 | 2.3.0 | CVE-2026-16636 | 2026-08-05 | Advisory |
| Medium 4.3 | <= 2.2.80 | 2.2.81 | CVE-2025-24739 | 2025-01-24 | Advisory |
| Critical 9.8 | <= 2.2.82 | 2.2.83 | CVE-2024-9511 | 2024-11-22 | Advisory |
| High 7.2 | <= 2.2.4 | 2.2.5 | CVE-2023-3087 | 2023-07-06 | Advisory |
| Low 3.8 | <= 2.2.2 | 2.2.3 | CVE-2023-0219 | 2023-03-03 | Advisory |
| Medium 5.5 | < 2.0.1 | 2.0.1 | CVE-2021-24528 | 2021-07-29 | Advisory |
Check if a site is affected
Enter a site address to see which version of FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP and other plugins it runs, and whether they match a known vulnerability.
Questions
Is the FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP plugin safe to use?
All 6 known issues are fixed in current versions (2.3.0 or later). Keeping it updated is what matters.
How do I check which version of FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP my site runs?
In WordPress go to Plugins > Installed Plugins. From the outside, the free PluginPeek scan below reads the version from the site's public files.
How do I fix a vulnerable plugin?
Make a full backup, then update it from Dashboard > Updates and check the site afterwards. If you would rather not, we can do it for a fixed $99, paid after you have checked the site.