CVE-2026-40308 (GCVE-0-2026-40308)
Vulnerability from cvelistv5
Published
2026-04-16 21:30
Modified
2026-04-17 12:32
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Summary
My Calendar is a WordPress plugin for managing calendar events. In versions 3.7.6 and below, the mc_ajax_mcjs_action AJAX endpoint, registered for unauthenticated users, passes user-supplied arguments through parse_str() without validation, allowing injection of arbitrary parameters including a site value. On WordPress Multisite installations, this enables an unauthenticated attacker to call switch_to_blog() with an arbitrary site ID and extract calendar events from any sub-site on the network, including private or hidden events. On standard Single Site installations, switch_to_blog() does not exist, causing an uncaught PHP fatal error and crashing the worker thread, creating an unauthenticated denial of service vector. This issue has been fixed in version 3.7.7.
Impacted products
Vendor Product Version
joedolson my-calendar Version: < 3.7.7
Create a notification for this product.
Show details on NVD website


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