GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-78006 (GCVE-0-2026-78006)

Vulnerability from cvelistv5 – Published: 2026-09-12 07:39 – Updated: 2026-09-12 07:39
VLAI
Title
The Events Calendar <= 6.17.4 - Unauthenticated PHP Object Injection to Remote Code Execution
Summary
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.
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-502 - Deserialization of Untrusted Data
Assigner
References
Impacted products
Vendor Product Version CPE status
stellarwp The Events Calendar Affected: 0 , ≤ 6.17.4 (semver)
guessed Create a notification for this product.
Credits
Chloe Chamberland Wordfence Argus
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "The Events Calendar",
          "vendor": "stellarwp",
          "versions": [
            {
              "lessThanOrEqual": "6.17.4",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Chloe Chamberland"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Wordfence Argus"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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\u0027s 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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-502",
              "description": "CWE-502 Deserialization of Untrusted Data",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-12T07:39:15.165Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
      "references": [
        {
          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/a0c67346-534a-4b67-a904-fa148703707a?source=cve"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Template_Bootstrap.php#L213"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Widgets/Service_Provider.php#L295"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Widgets/Service_Provider.php#L255"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Collections/Lazy_Post_Collection.php#L82"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/common/src/Tribe/Utils/Collection_Trait.php#L247"
        },
        {
          "url": "https://plugins.trac.wordpress.org/changeset?reponame=\u0026old=3690576%40the-events-calendar\u0026new=3690576%40the-events-calendar"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-08-21T22:52:17.000Z",
          "value": "Vendor Notified"
        },
        {
          "lang": "en",
          "time": "2026-09-11T18:39:45.000Z",
          "value": "Disclosed"
        }
      ],
      "title": "The Events Calendar \u003c= 6.17.4 - Unauthenticated PHP Object Injection to Remote Code Execution"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
    "assignerShortName": "Wordfence",
    "cveId": "CVE-2026-78006",
    "datePublished": "2026-09-12T07:39:15.165Z",
    "dateReserved": "2026-08-21T21:25:40.295Z",
    "dateUpdated": "2026-09-12T07:39:15.165Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-78006\",\"sourceIdentifier\":\"security@wordfence.com\",\"published\":\"2026-09-12T08:16:24.240\",\"lastModified\":\"2026-09-12T08:16:24.240\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"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\u0027s 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.\"}],\"affected\":[{\"source\":\"security@wordfence.com\",\"affectedData\":[{\"vendor\":\"stellarwp\",\"product\":\"The Events Calendar\",\"defaultStatus\":\"unaffected\",\"versions\":[{\"version\":\"0\",\"lessThanOrEqual\":\"6.17.4\",\"versionType\":\"semver\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security@wordfence.com\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":9.8,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"security@wordfence.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-502\"}]}],\"references\":[{\"url\":\"https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/common/src/Tribe/Utils/Collection_Trait.php#L247\",\"source\":\"security@wordfence.com\"},{\"url\":\"https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Collections/Lazy_Post_Collection.php#L82\",\"source\":\"security@wordfence.com\"},{\"url\":\"https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Template_Bootstrap.php#L213\",\"source\":\"security@wordfence.com\"},{\"url\":\"https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Widgets/Service_Provider.php#L255\",\"source\":\"security@wordfence.com\"},{\"url\":\"https://plugins.trac.wordpress.org/browser/the-events-calendar/tags/6.17.3/src/Tribe/Views/V2/Widgets/Service_Provider.php#L295\",\"source\":\"security@wordfence.com\"},{\"url\":\"https://plugins.trac.wordpress.org/changeset?reponame=\u0026old=3690576%40the-events-calendar\u0026new=3690576%40the-events-calendar\",\"source\":\"security@wordfence.com\"},{\"url\":\"https://www.wordfence.com/threat-intel/vulnerabilities/id/a0c67346-534a-4b67-a904-fa148703707a?source=cve\",\"source\":\"security@wordfence.com\"}]}}"
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.