The Event Registration Calendar By vcita plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's shortcodes in all versions up to, and including, 1.4.0 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Event Registration Calendar By vcita plugin, versions up to and including 3.9.1, and Online Payments – Get Paid with PayPal, Square & Stripe plugin, for WordPress are vulnerable to Cross-Site Request Forgery. This is due to missing nonce validation in the ls_parse_vcita_callback() function. This makes it possible for unauthenticated attackers to modify the plugin's settings and inject malicious JavaScript via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

The Event Registration Calendar By vcita plugin, versions up to and including 3.9.1, and Online Payments – Get Paid with PayPal, Square & Stripe plugin, for WordPress are vulnerable to Stored Cross-Site Scripting via the 'email' parameter in versions up to, and including, 1.3.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers with the edit_posts capability, such as contributors and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.