CVE-2026-97642: Wp Parsidate <= 6.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'theme' Block Attribute

The Wp Parsidate plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the calendar Gutenberg block's 'theme' attribute in versions up to, and including, 6.4. This is due to insufficient input sanitization and output escaping on the block attribute value which is concatenated directly into an HTML class attribute in the printCalendar() function without esc_attr(). 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.