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Modern Events Calendar Lite - Security Vulnerability (CVE-2021-24146)

CVE-2021-24146

Lack of authorisation checks in the Modern Events Calendar Lite WordPress plugin, versions before 5.16.5, did not properly restrict access to the export files, allowing unauthenticated users to exports all events data in CSV or XML format for example.

CVE-2021-24146

HIGH CVSS 7.5 Published 2021-03-18 Updated 2026-06-17
AI Risk Critical (94/100) Active Exploit: Likely Published Exploit: Public exploit references found Priority: P1 Immediate
Severity Band HIGH
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Affected Components 1
Reference Links 2
AI Risk Engine Critical (94/100)
Exploitability High
Active Exploitation Likely
Published Exploit Status Public exploit references found

Threat Timeline

  1. 2021-03-18 CVE published and first recorded in the threat feed.
  2. 2026-06-17 Record updated with latest vulnerability metadata.
  3. 2026-04-11 AI technical context refreshed for mitigation and impact guidance.
  4. Now Monitoring for follow-up changes, linked references, and new related CVEs.

AI Context

Machine-generated threat intelligence

AI Updated 173 days ago

AI enriched 173 days ago (2026-04-11 00:12 UTC)

Technical Summary

Lack of authorisation checks in the Modern Events Calendar Lite WordPress plugin, versions before 5.16.5, did not properly restrict access to the export files, allowing unauthenticated users to exports all events data in CSV or XML format for example.

Potential Impact

Severity is HIGH (CVSS 7.5). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as High based on published exploit references, low-bar exploit prerequisites.

Primary risk drivers: published exploit references, low-bar exploit prerequisites

Mitigation Recommendations

Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.

Detection & Monitoring

Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.

Business Impact Lens

AI risk score 94/100 (Critical, High) with priority P1 Immediate. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.

References

What to do about this

Patch promptly The consequence is significant even where an attacker needs a foothold first.

Fix it

Update Modern Events Calendar Lite to 5.16.5 or later.

That is the complete fix. Everything below is what protects you in the meantime.

No Hack Halt control meaningfully contains this one — updating is the remedy. We would rather say so than sell you something that will not help.

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Not sure if you are affected?

Scan your site to see whether it runs Modern Events Calendar Lite, and at which version.

Free, no installation, no account. It reads what your site already publishes, then tells you which plugins carry known vulnerabilities and what to do about each one.

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Am I affected by this vulnerability?

You are affected if your site runs Modern Events Calendar Lite. Versions below 5.16.5 are vulnerable; that release and later are not. No account is needed to exploit this, so a public site is reachable by anyone.

How do I fix it?

Update Modern Events Calendar Lite to version 5.16.5 or later. That is the complete fix.