WordPress plugin
FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP security & vulnerabilities
No known unpatched vulnerabilities in the latest version
All 6 known vulnerabilities are fixed in the latest release. If you run an older version, update to null or newer.
- Critical1
- High2
- Medium2
- Low1
All FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP vulnerabilities
| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| High7.2 | Unauthenticated Stored Cross-Site Scripting via Recipient Display Name (to.name) in Email Logs ≤2.2.95Update to 2.3.0 | CVE-2026-16636 | |
| Medium4.3 | Cross-Site Request Forgery ≤2.2.80Update to 2.2.81 | CVE-2025-24739 | |
| Critical9.8 | Unauthenticated PHP Object Injection ≤2.2.82Update to 2.2.83 | CVE-2024-9511 | |
| High7.2 | Unauthenticated Stored Cross-Site Scripting via Email Subject ≤2.2.4Update to 2.2.5 | CVE-2023-3087 | |
| Low3.8 | Authenticated (Author+) Stored Cross-Site Scripting via Email Logs ≤2.2.2Update to 2.2.3 | CVE-2023-0219 | |
| Medium5.5 | Authenticated (Admin+) Stored Cross-Site Scripting <2.0.1Update to 2.0.1 | CVE-2021-24528 |
- High7.2Unauthenticated Stored Cross-Site Scripting via Recipient Display Name (to.name) in Email Logs
≤2.2.95Update to 2.3.0
- Medium4.3Cross-Site Request Forgery
≤2.2.80Update to 2.2.81
- Critical9.8Unauthenticated PHP Object Injection
≤2.2.82Update to 2.2.83
- High7.2Unauthenticated Stored Cross-Site Scripting via Email Subject
≤2.2.4Update to 2.2.5
- Low3.8Authenticated (Author+) Stored Cross-Site Scripting via Email Logs
≤2.2.2Update to 2.2.3
- Medium5.5Authenticated (Admin+) Stored Cross-Site Scripting
<2.0.1Update to 2.0.1
FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP: common questions
Does FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP have known vulnerabilities?
Yes. VulnCrest Radar lists 6 known vulnerabilities in FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP: 1 critical, 2 high, 2 medium, 1 low. None are known to affect version null.
How do I check which version of FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP I run?
In wp-admin open Plugins → Installed Plugins; the version is shown under the name. Without admin access, our passive Check my site tool can often read it from public files.
What is the most recent FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP vulnerability?
CVE-2026-16636, published Aug 5, 2026: FluentSMTP <= 2.2.95 - Unauthenticated Stored Cross-Site Scripting via Recipient Display Name (to.name) in Email Logs. Severity: High (CVSS 7.2).
Is any FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP vulnerability listed in CISA KEV?
No. None of the known FluentSMTP – WP Mail SMTP Plugin with Amazon SES, SendGrid, Mailgun, Postmark, Cloudflare, toSend, Gmail and Any SMTP vulnerabilities is currently listed in the CISA KEV catalog.