The EventON - Subscriber plugin for WordPress is vulnerable to generic SQL Injection via the 'email' parameter in all versions up to, and including, 1.4.5 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.

The EventON Action User plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 2.5.14. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for unauthenticated attackers to grant EventON management capabilities and the uploadfiles capability to any non-administrator WordPress role or user, escalating their privileges within the site. The administrator role is protected by an early-return guard in updaterolecaps(), so only non-administrator roles and individual users can be targeted; however, the same unauthenticated exposure also allows attackers to enumerate all WordPress users with their IDs and display names, disclose role and user capability state along with nonce values, and tamper with event-to-user term assignments.

The EventON Pro plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check in the 'assets/lib/settings/settings.js' file in all versions up to, and including, 4.9.6. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The vulnerability was partially patched in version 4.9.6.

The EventON WordPress plugin before 2.2.15 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 EventON plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the 'eventonimportsettings' ajax action in all versions up to, and including, 2.2.15. This makes it possible for unauthenticated attackers to update plugin settings, including adding stored cross-site scripting to settings options displayed on event calendar pages.