HomeWordPress vulnerabilitiesFluentSMTP
FluentSMTP vulnerabilities
FluentSMTP has 5 known vulnerabilities in this database. The most recent published record is dated 6 Aug 2026.
- Known vulnerabilities
- 5
- Active installs
- 700,000+
- Latest version
- 2.4.1
- Last updated
- 27 Sep 2026
- Most recent
- 6 Aug 2026
Find it in your WordPress dashboard under Plugins. Severity is based on the CVSS score published with the CVE where one is available.
| Vulnerability | Severity | Affected | Fix | Published |
|---|---|---|---|---|
| Cross-site scripting (XSS) CVE-2026-16636 | High 7.2 | Up to 2.2.95 | Fixed in a later version (latest 2.4.1) | 6 Aug 2026 |
| PHP object injection CVE-2024-9511 | Critical 9.8 | Up to 2.2.82 | Fixed in a later version (latest 2.4.1) | 23 Nov 2024 |
| Cross-site scripting (XSS) CVE-2023-3087 | High 7.2 | Before 2.2.5 | Fixed in 2.2.5 | 12 Jul 2023 |
| Cross-site scripting (XSS) CVE-2023-0219 | Medium 5.4 | Before 2.2.3 | Fixed in 2.2.3 | 13 Mar 2023 |
| Cross-site scripting (XSS) CVE-2021-24528 | Medium 5.4 | Before 2.0.1 | Fixed in 2.0.1 | 30 Aug 2021 |
Read the published descriptions
- CVE-2026-16636, 6 Aug 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. CVE record
- CVE-2024-9511, 23 Nov 2024
- The FluentSMTP - WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 2.2.82 via deserialization of untrusted input in the 'formatResult' function. This makes it possible for unauthenticated attackers to inject a PHP Object. No known POP chain is present in the vulnerable software. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code. The vulnerability was partially patched in version 2.2.82. CVE record
- CVE-2023-3087, 12 Jul 2023
- The FluentSMTP plugin for WordPress is vulnerable to Stored Cross-Site Scripting via an email subject in versions up to, and including, 2.2.4 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. CVE record
- CVE-2023-0219, 13 Mar 2023
- The FluentSMTP WordPress plugin before 2.2.3 does not sanitize or escape email content, making it vulnerable to stored cross-site scripting attacks (XSS) when an administrator views the email logs. This exploit requires other plugins to enable users to send emails with unfiltered HTML. CVE record
- CVE-2021-24528, 30 Aug 2021
- The FluentSMTP WordPress plugin before 2.0.1 does not sanitize parameters before storing the settings in the database, nor does the plugin escape the values before outputting them when viewing the SMTP settings set by this plugin, leading to a stored cross site scripting (XSS) vulnerability. Only users with roles capable of managing plugins can modify the plugin's settings. CVE record
What to do if you run FluentSMTP
If you run FluentSMTP, open WordPress and check the installed version in Plugins. Compare it with the affected versions in the vulnerability record. If a fixed version is available, take a current backup and update to that version or the latest supported release.
If no fixed version exists, consider disabling and removing the plugin or replacing it with a maintained alternative. After dealing with the affected software, check administrator users, unexpected file changes, redirects, unfamiliar pages and security logs for signs that the site may already have been altered.
Email me about new FluentSMTP vulnerabilities
Free. We email you when a new vulnerability is published for FluentSMTP, usually within minutes. Confirm by email; unsubscribe any time.
Focus on your business. We’ll take care of your website.
From everyday updates to ongoing care, we keep your website working.