CVE-2021-24149: Unvalidated input in the Modern Events Calendar Lite WordPress plugin, versions before 5.16.6, did not sanitise the mec[post_id] POST parameter in the mec_fes_form AJAX action when logged in as an aut

high Affects modern-events-calendar-lite (WordPress plugin). Feed 2026.10.29.1, updated 2026-10-28; published 2021-03-18; advisory modified 2026-06-17.

Unvalidated input in the Modern Events Calendar Lite WordPress plugin, versions before 5.16.6, did not sanitise the mec[post_id] POST parameter in the mec_fes_form AJAX action when logged in as an aut

Package: modern-events-calendar-lite (WordPress plugin) WordPress
Affected versions: <5.16.6
Fixed in: 5.16.6
Severity: high CVSS 8.8
Exploitation: not on CISA KEV · EPSS 2% (74.3th percentile)
Published: 2021-03-18
Source: nvd

References

CWE-89

NVD record modern-events-calendar-lite (WordPress plugin) advisories

Am I affected?

Find out in one command. phpwarden checks your WordPress install against this advisory and 20,000+ others, ranked by real-world exploitation (CISA KEV + EPSS). Free, offline, open data.

# one-time install
pip install phpwarden

# then
phpwarden wordpress /var/www/html

Or keep it checked automatically with the GitHub Action or a nightly cron; see WordPress docs.

Install docs How findings are ranked

Related advisories

CVE-2021-24145 high Arbitrary file upload in the Modern Events Calendar Lite WordPress plugin, versions before same package: modern-events-calendar-lite (WordPress plugin)
CVE-2021-24946 critical The Modern Events Calendar Lite WordPress plugin before 6.1.5 does not sanitise and escape same package: modern-events-calendar-lite (WordPress plugin)
CVE-2022-0364 medium The Modern Events Calendar Lite WordPress plugin before 6.4.0 does not sanitize and escape same package: modern-events-calendar-lite (WordPress plugin)
CVE-2021-24146 high Lack of authorisation checks in the Modern Events Calendar Lite WordPress plugin, versions same package: modern-events-calendar-lite (WordPress plugin)
CVE-2024-5441 high The Modern Events Calendar plugin for WordPress is vulnerable to arbitrary file uploads du same package: modern-events-calendar-lite (WordPress plugin)
CVE-2020-9459 medium Multiple Stored Cross-site scripting (XSS) vulnerabilities in the Webnus Modern Events Cal same package: modern-events-calendar-lite (WordPress plugin)