The Easy WP SMTP plugin for WordPress is vulnerable to authorization bypass in versions up to, and including, 1.3.9. This is due to missing capability checks on the admin_init() function, in addition to insufficient input validation. This makes it possible for unauthenticated attackers to modify the plugins settings and arbitrary options on the site that can be used to inject new administrative user accounts.

The Newsletter, SMTP, Email marketing and Subscribe forms by Sendinblue WordPress plugin before 3.1.61 does not sanitise and escape a parameter before outputting it back in the admin dashboard when the WPML plugin is also active and configured, leading to a Reflected Cross-Site Scripting which could be used against high privilege users such as admin

The SMTP Mailing Queue WordPress plugin before 2.0.1 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup)

ascii_load_sockaddr in smtpd in OpenBSD before 7.1 errata 024 and 7.2 before errata 020, and OpenSMTPD Portable before 7.0.0-portable commit f748277, can abort upon a connection from a local, scoped IPv6 address.

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.

Auth. Remote Code Execution vulnerability in Easy WP SMTP plugin <= 1.5.1 on WordPress.

Auth. Path Traversal vulnerability in Easy WP SMTP plugin <= 1.5.1 on WordPress.

Auth. Path Traversal vulnerability in Easy WP SMTP plugin <= 1.5.1 at WordPress.

The Easy WP SMTP WordPress plugin before 1.5.0 unserialises the content of an imported file, which could lead to PHP object injection issue when an admin import (intentionally or not) a malicious file and a suitable gadget chain is present on the blog.

The Post SMTP Mailer/Email Log WordPress plugin before 2.1.7 does not have proper authorisation in some AJAX actions, which could allow high privilege users such as admin to perform blind SSRF on multisite installations for example.