Vulnerabilities and security researches forfluent-smtp fluent-smtp

Jun 06, 2024

CVE, Research URL: CVE-2023-3087
Home page URL: Security reports for FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Application: FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Date: Jul 12, 2023
Research Description: 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.
Affected versions: max 2.2.5.
Status: vulnerable

CVE, Research URL: CVE-2023-0219
Home page URL: Security reports for FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Application: FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Date: Mar 13, 2023
Research Description: 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.
Affected versions: max 2.2.3.
Status: vulnerable

CVE, Research URL: CVE-2021-24528
Home page URL: Security reports for FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Application: FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Date: Aug 30, 2021
Research Description: 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.
Affected versions: max 2.0.1.
Status: vulnerable

Nov 24, 2024

CVE, Research URL: CVE-2024-9511
Home page URL: Security reports for FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Application: FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Date: Nov 23, 2024
Research Description: 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.
Affected versions: max 2.2.83.
Status: vulnerable

Jan 26, 2025

CVE, Research URL: CVE-2025-24739
Home page URL: Security reports for FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Application: FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Date: Jan 24, 2025
Research Description: Cross-Site Request Forgery (CSRF) vulnerability in FluentSMTP & WPManageNinja Team FluentSMTP allows Cross Site Request Forgery. This issue affects FluentSMTP: from n/a through 2.2.80.
Affected versions: max 2.2.81.
Status: vulnerable

May 26, 2026

PSC, Research URL: PSC-2026-64658
Home page URL: Security reports for FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Application: FluentSMTP – WP Mail SMTP, Amazon SES, SendGrid, MailGun and Any SMTP Connector Plugin
Date: May 26, 2026
Research Description: SMTP and email routing plugins hold highly sensitive operational data because they connect WordPress to external mail infrastructure, API credentials, OAuth-based providers, email logs, and resend workflows. Weak controls in this layer can expose tokens, disclose private email content, alter transactional mail routing, or allow unauthorized users to resend messages. FluentSMTP version 2.2.95 has successfully completed the CleanTalk Plugin Security Certification process and received PSC-2026-64658, confirming that the plugin was reviewed from a secure code perspective with attention to common exploitation paths for mail delivery and email logging plugins.
Affected versions: Min 2.2.95, max 2.2.95.
Status: SAFE & CERTIFIED