Answer in brief
CVE-2026-78006 records a Unknown severity vulnerability in The Events Calendar <= 6.17.4 - Unauthenticated PHP Object Injection to Remote Code Execution. The current sources do not mark it as known exploited. The current feed maps stellarwp/The Events Calendar (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps stellarwp/The Events Calendar (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| stellarwp/The Events Calendargeneric | 0 | Not reported |
Published upstream
Sep 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 12, 2026
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.
Quoted source text, attributed separately from HOL analysis.