Stored Cross-Site Scripting in XO Event Calendar Plugin for WordPress

CVE-2026-0556

What is CVE-2026-0556?

The XO Event Calendar plugin for WordPress allows authenticated users with contributor level access and above to exploit a vulnerability present in the 'xo_event_field' shortcode. An attacker can inject arbitrary web scripts into pages due to inadequate input sanitization and output escaping on user-supplied attributes. This results in potentially malicious scripts being executed when users access affected pages, leading to severe security risks, including data theft and site compromise.

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