My Calendar WordPress plugin 3.8.8 before 3.8.11 contains a shortcode injection vulnerability that allows unauthenticated attackers to execute registered shortcodes via the mcs search parameter. The mcs value reaches mc_search_results() in src/my-calendar-search.php without bracket encoding before do_shortcode runs, so a GET request triggers shortcodes on any page or post, enabling content injection and spoofing.
Fix
Patch, vendor advisory and mitigation references on NVD 1
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 6.9 · joedolsonNVD modified 2026-10-30 15:42
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 5
- https://github.com/joedolson/my-calendar/commit/de875c25d9651abb041b2dfe32f60a4320c66496 patch
- https://github.com/joedolson/my-calendar product
- https://github.com/joedolson/my-calendar/releases/tag/v3.8.11 release-notes
- https://github.com/joedolson/my-calendar/blob/v3.8.10/src/my-calendar-search.php#L170 technical-description
- https://www.vulncheck.com/advisories/my-calendar-3.8.8-before-3.8.11-unauthenticated-shortcode-injection-via-mcs-parameter third-party-advisory