XSS in Webnus Modern Events Calendar Lite

CVE-2021-24147

Unvalidated input and lack of output encoding in the Modern Events Calendar Lite WordPress plugin, versions before 5.16.5, did not sanitise the mic_comment field (Notes on time) when adding/editing an event, allowing users with privilege as low as author to add events with a Cross-Site Scripting payload in them, which will be triggered in the frontend when viewing the event.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.007 (51.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-24147?
CVE-2021-24147 is a medium-severity vulnerability in Webnus Modern Events Calendar Lite, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2021-03-18.
How severe is CVE-2021-24147?
Medium severity. CVSS v3 base score is 5.4 out of 10.
Is CVE-2021-24147 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.