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.

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.

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.

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.

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.