The SendPress Newsletters WordPress plugin through 1.26.1.20 does not check the user's capability on several newsletter-management actions, allowing any authenticated subscriber-level user to synchronise all site users into a mailing list and to drive the newsletter send queue.

The SendPress Newsletters WordPress plugin through 1.23.11.6 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 unfilteredhtml capability is disallowed (for example in multisite setup)

The SendPress Newsletters WordPress plugin through 1.23.11.6 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 unfilteredhtml capability is disallowed (for example in multisite setup)