My Calendar – Accessible Event Manager

The My Calendar – Accessible Event Manager plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 3.8.7. The public `mcs` GET parameter is reflected into post content unsanitized before WordPress core's `do_shortcode` filter runs, allowing an unauthenticated attacker to inject a nested `[my_calendar above=...]` shortcode; `mc_generate_calendar_nav()` then splits the `above` attribute on commas and dispatches each element via `call_user_func()` with no authentication, authorization, or callable allowlist check. This makes it possible for unauthenticated attackers to invoke arbitrary loaded PHP functions, enabling a call chain in which the shortcode `$params` array is passed to `edit_user()` — which PHP coerces to integer `1` as the `$user_id` argument — overwriting the credentials of the initial Administrator account (user ID 1) and granting the attacker full wp-admin access. Exploitation is trivially reachable via the plugin's auto-generated `/my-calendar/` page, which is publicly accessible by default upon plugin activation.

Published: 2026-10-16T04:27:04.876Z
Updated: 2026-10-16T17:07:17.621Z

The My Calendar – Accessible Event Manager plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'fallback' Shortcode Attribute in all versions up to, and including, 3.8.3 due to insufficient input sanitization and output escaping. 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 bypass relies on hex-encoded shortcode attribute payloads (e.g. \x3cscript\x3e), which wp_kses_post cannot strip on save because they appear as literal backslash sequences rather than real HTML tags; WordPress core's shortcode_parse_atts() then calls stripcslashes() at render time, decoding the escapes into real angle brackets before they reach the unescaped sink.

Published: 2026-09-09T03:28:47.091Z
Updated: 2026-09-09T13:12:36.335Z

The My Calendar – Accessible Event Manager plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'before' and 'after' Shortcode Attributes in all versions up to, and including, 3.8.3 due to insufficient input sanitization and output escaping. 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.

Published: 2026-09-09T03:28:47.465Z
Updated: 2026-09-11T20:19:14.864Z

The My Calendar – Accessible Event Manager plugin for WordPress is vulnerable to time-based blind SQL Injection via the 'mc_auth' parameter in all versions up to, and including, 3.7.8 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.

Published: 2026-07-08T11:30:33.597Z
Updated: 2026-07-08T13:14:04.081Z

The My Calendar – Accessible Event Manager plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 3.7.14 via the 'vcal' parameter due to missing validation on a user controlled key. This makes it possible for unauthenticated attackers to enumerate occurrence IDs and access the full iCalendar export of non-public, draft, trashed, and personal calendar events, disclosing sensitive event metadata including titles, descriptions, dates, locations, organizer and host details, permalinks, and related calendar metadata.

Published: 2026-07-02T08:33:06.892Z
Updated: 2026-07-02T19:42:08.293Z