{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-40308","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-04-10T21:41:54.504Z","datePublished":"2026-04-16T21:30:52.401Z","dateUpdated":"2026-04-17T12:32:26.622Z"},"containers":{"cna":{"title":"My Calendar: Unauthenticated Information Disclosure (IDOR) via Multisite switch_to_blog","problemTypes":[{"descriptions":[{"cweId":"CWE-639","lang":"en","description":"CWE-639: Authorization Bypass Through User-Controlled Key","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/joedolson/my-calendar/security/advisories/GHSA-2mvx-f5qm-v2ch","tags":["x_refsource_CONFIRM"],"url":"https://github.com/joedolson/my-calendar/security/advisories/GHSA-2mvx-f5qm-v2ch"},{"name":"https://github.com/joedolson/my-calendar/releases/tag/v3.7.7","tags":["x_refsource_MISC"],"url":"https://github.com/joedolson/my-calendar/releases/tag/v3.7.7"}],"affected":[{"vendor":"joedolson","product":"my-calendar","versions":[{"version":"< 3.7.7","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-04-16T21:30:52.401Z"},"descriptions":[{"lang":"en","value":"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."}],"source":{"advisory":"GHSA-2mvx-f5qm-v2ch","discovery":"UNKNOWN"}},"adp":[{"references":[{"url":"https://github.com/joedolson/my-calendar/security/advisories/GHSA-2mvx-f5qm-v2ch","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-17T12:32:21.737938Z","id":"CVE-2026-40308","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-04-17T12:32:26.622Z"}}]}}