{"schemaVersion":3,"id":"CVE-2026-104798","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"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.","dates":{"published":"2026-10-16T04:27:04.876Z","modified":"2026-10-16T17:07:17.621Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.8,"severity":"critical","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":9.8,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":9.8,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00891,"percentile":0.5894,"severity":"low","asOf":"2026-10-21T00:00:00.000Z","change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[{"date":"2026-10-16T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.00891,"percentile":0.5894}],"last30":[{"date":"2026-10-16T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00891,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.00891,"percentile":0.5894}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-269","name":"Improper Privilege Management","description":"The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.","type":"weakness","status":"Draft","abstraction":"Class","likelihoodOfExploit":"Medium","url":"https://cwe.mitre.org/data/definitions/269.html"}],"affected":[{"vendor":"joedolson","product":"my calendar – accessible event manager","name":"My Calendar – Accessible Event Manager","label":"my calendar – accessible event manager","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≤ 3.4.24","noFixRecorded":false,"fixedIn":null},{"text":"≥ 3.5, ≤ 3.5.21","noFixRecorded":false,"fixedIn":null},{"text":"≥ 3.6, ≤ 3.6.17","noFixRecorded":false,"fixedIn":null},{"text":"≥ 3.7, ≤ 3.7.17","noFixRecorded":false,"fixedIn":null},{"text":"≥ 3.8, ≤ 3.8.7","noFixRecorded":false,"fixedIn":null}],"versionsText":"≤ 3.4.24 | ≥ 3.5, ≤ 3.5.21 | ≥ 3.6, ≤ 3.6.17 | ≥ 3.7, ≤ 3.7.17 | ≥ 3.8, ≤ 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