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CVE-2026-78159 (GCVE-0-2026-78159)

Vulnerability from cvelistv5 – Published: 2026-09-12 07:39 – Updated: 2026-09-12 07:39
VLAI
Title
The Events Calendar <= 6.17.3 - Unauthenticated Code Injection to Remote Code Execution via Widget 'classes' Map Callable Invocation
Summary
The The Events Calendar plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 6.17.3 via the parse_array function. This is due to insufficient validation of the widget 'classes' map, allowing a plain-array payload to bypass the is_safe_widget_instance() object check and reach the callable-invocation sink in Element_Classes::parse_array(). This makes it possible for unauthenticated attackers to execute code on the server. Exploitation requires that the targeted site has comments enabled on tribe_events posts and that at least one comment containing a crafted wp:legacy-widget block has been submitted, as the attack chain is triggered when do_blocks() processes the single-event HTML including the comment area.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
Assigner
References
Impacted products
Vendor Product Version CPE status
stellarwp The Events Calendar Affected: 0 , ≤ 6.17.3 (semver)
guessed Create a notification for this product.
Credits
Chloe Chamberland Wordfence Argus
Show details on NVD website
To clipboard 

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          "vendor": "stellarwp",
          "versions": [
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          "lang": "en",
          "type": "finder",
          "value": "Chloe Chamberland"
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        }
      ],
      "metrics": [
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        "dateUpdated": "2026-09-12T07:39:15.542Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
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        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/common/src/Tribe/Utils/Element_Classes.php#L211"
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          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/views/v2/components/messages.php#L30"
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          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Widgets/Service_Provider.php#L279"
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          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Template_Bootstrap.php#L214"
        },
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          "url": "https://plugins.trac.wordpress.org/changeset?reponame=\u0026old=3667866%40the-events-calendar\u0026new=3667866%40the-events-calendar"
        },
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          "url": "https://plugins.trac.wordpress.org/changeset?reponame=\u0026old=3667867%40the-events-calendar\u0026new=3667867%40the-events-calendar"
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      "timeline": [
        {
          "lang": "en",
          "time": "2026-08-23T11:54:47.000Z",
          "value": "Vendor Notified"
        },
        {
          "lang": "en",
          "time": "2026-09-11T18:40:37.000Z",
          "value": "Disclosed"
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      "title": "The Events Calendar \u003c= 6.17.3 - Unauthenticated Code Injection to Remote Code Execution via Widget \u0027classes\u0027 Map Callable Invocation"
    }
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    "datePublished": "2026-09-12T07:39:15.542Z",
    "dateReserved": "2026-08-23T11:39:39.155Z",
    "dateUpdated": "2026-09-12T07:39:15.542Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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  }
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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