Cyber Resilience

CVE-2021-24147

MediumPublic PoC

Published: 18 March 2021

Published
18 March 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0027 50.4th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-24147 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Webnus Modern Events Calendar Lite. Its CVSS base score is 5.4 (Medium).

Operationally, ranked in the top 49.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

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…

more

add events with a Cross-Site Scripting payload in them, which will be triggered in the frontend when viewing the event.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

webnus
modern events calendar lite
≤ 5.16.5

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References