The Events Calendar - Security Vulnerability (CVE-2026-78006)

CVE-2026-78006

Vulnerability CVE-2026-78006 PLUGIN events-calendar CRITICAL

The The Events Calendar plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 6.17.4 via the is_safe_widget_instance function. This is due to insufficient protection in is_safe_widget_instance, which can be bypassed because PHP fires magic methods during its pre-parse, combined with enable_rendering_widget_copied() forging a valid wp_hash integrity attribute before unserialize() is reached. This makes it possible for unauthenticated attackers to execute code on the server. This is exploitable without authentication or approval because the plugin's V2 single-event template runs do_blocks() over buffered comment HTML, and WordPress returns a moderation-hash URL that allows an unauthenticated commenter to immediately view their own pending comment, delivering the injected block markup to the vulnerable code path before any moderation occurs. This does require comments to be enabled and visible on events.

CVE-2026-78006

CRITICAL CVSS 9.8 Published 2026-09-12 Updated 2026-09-14

AI Risk Critical (100/100) Active Exploit: No strong signal Published Exploit: No public exploit references Priority: P1 Immediate

Severity Band CRITICAL

CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Components 1

Reference Links 7

AI Risk Engine Critical (100/100)

Exploitability Very High

Active Exploitation No strong signal

Published Exploit Status No public exploit references

Threat Timeline

2026-09-12 CVE published and first recorded in the threat feed.
2026-09-14 Record updated with latest vulnerability metadata.
2026-09-19 AI technical context refreshed for mitigation and impact guidance.
Now Monitoring for follow-up changes, linked references, and new related CVEs.

AI Context

Machine-generated threat intelligence

AI Updated 46 days ago

AI enriched 46 days ago (2026-09-19 19:45 UTC)

Technical Summary

Potential Impact

Severity is CRITICAL (CVSS 9.8). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as Very High based on remote code execution potential, low-bar exploit prerequisites.

Primary risk drivers: remote code execution potential, 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 100/100 (Critical, Very High) with priority P1 Immediate. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.

Affected Products

The Events Calendar PLUGIN · events-calendar Affected range not specified Fixed version not specified

References

What to do about this

Patch immediately Serious, and reachable without meaningful privilege.

Fix it

Update The Events Calendar to the latest available version.

Where the vendor has not published a fix yet, disable the plugin until they do.

Cannot update today? Request / payload inspection (WAF) in Hack Halt ProSecure blocks this class of attack before WordPress processes the request.

Inspect request parameters and bodies for injection, traversal and file-inclusion payloads, and refuse the request rather than logging it.

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Not sure if you are affected?

Scan your site to see whether it runs The Events Calendar, 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 The Events Calendar. No account is needed to exploit this, so a public site is reachable by anyone.

How do I fix it?

Update The Events Calendar to the latest available version. Where the vendor has not yet published a fix, remove or disable the plugin until they do. Until you can update, Request / payload inspection (WAF) in Hack Halt ProSecure contains this class of attack at the request layer.

What can an attacker actually do?

This is a Remote Code Execution flaw. An attacker who exploits it can run their own code on the server, which is total control of the site.