Vulnerability-Lookup

GHSA-F53P-382V-8PJ7

Vulnerability from github – Published: 2026-05-21 06:31 – Updated: 2026-05-21 06:31

Details

The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions up to and including 3.15.2. This is due to the wp_conditional_tags case in Fusion_Builder_Conditional_Render_Helper::get_value() passing attacker-controlled values from a base64-decoded JSON blob directly to call_user_func() without any allowlist validation. This is exploitable by unauthenticated attackers through the fusion_get_widget_markup AJAX endpoint, which is registered for non-privileged (unauthenticated) users via wp_ajax_nopriv_fusion_get_widget_markup. The endpoint is protected only by a nonce (fusion_load_nonce), but this nonce is generated for user ID 0 and is deterministically exposed in the JavaScript output of any public-facing page containing a Post Cards ([fusion_post_cards]) or Table of Contents ([fusion_table_of_contents]) element. This makes it possible for unauthenticated attackers to execute arbitrary code on affected sites.

Severity

9.8 (Critical)


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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-6279"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-74"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-21T05:16:23Z",
    "severity": "CRITICAL"
  },
  "details": "The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions up to and including 3.15.2. This is due to the `wp_conditional_tags` case in `Fusion_Builder_Conditional_Render_Helper::get_value()` passing attacker-controlled values from a base64-decoded JSON blob directly to `call_user_func()` without any allowlist validation. This is exploitable by unauthenticated attackers through the `fusion_get_widget_markup` AJAX endpoint, which is registered for non-privileged (unauthenticated) users via `wp_ajax_nopriv_fusion_get_widget_markup`. The endpoint is protected only by a nonce (`fusion_load_nonce`), but this nonce is generated for user ID 0 and is deterministically exposed in the JavaScript output of any public-facing page containing a Post Cards (`[fusion_post_cards]`) or Table of Contents (`[fusion_table_of_contents]`) element. This makes it possible for unauthenticated attackers to execute arbitrary code on affected sites.",
  "id": "GHSA-f53p-382v-8pj7",
  "modified": "2026-05-21T06:31:31Z",
  "published": "2026-05-21T06:31:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6279"
    },
    {
      "type": "WEB",
      "url": "https://avada.com/documentation/avada-changelog"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/class-fusion-builder.php#L7551"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1083"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1531"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/shortcodes/fusion-widget.php#L389"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/shortcodes/fusion-widget.php#L44"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/class-fusion-builder.php#L7551"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1083"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1531"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/shortcodes/fusion-widget.php#L389"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/shortcodes/fusion-widget.php#L44"
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/5dc72d78-d47c-4b36-8d69-8672e15ddf8c?source=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-6279 (GCVE-0-2026-6279)

Vulnerability from cvelistv5 – Published: 2026-05-21 04:27 – Updated: 2026-05-21 12:23

Title

Avada (Fusion) Builder <= 3.15.2 - Unauthenticated Remote Code Execution via PHP Function Injection via 'render_logics' Shortcode Attribute via Widget AJAX Handler

Summary

The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions up to and including 3.15.2. This is due to the `wp_conditional_tags` case in `Fusion_Builder_Conditional_Render_Helper::get_value()` passing attacker-controlled values from a base64-decoded JSON blob directly to `call_user_func()` without any allowlist validation. This is exploitable by unauthenticated attackers through the `fusion_get_widget_markup` AJAX endpoint, which is registered for non-privileged (unauthenticated) users via `wp_ajax_nopriv_fusion_get_widget_markup`. The endpoint is protected only by a nonce (`fusion_load_nonce`), but this nonce is generated for user ID 0 and is deterministically exposed in the JavaScript output of any public-facing page containing a Post Cards (`[fusion_post_cards]`) or Table of Contents (`[fusion_table_of_contents]`) element. This makes it possible for unauthenticated attackers to execute arbitrary code on affected sites.

Severity

9.8 (Critical)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-21 12:22 UTC

CWE

CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Assigner

Wordfence mitre root

References

12 references

URL	Tags
https://www.wordfence.com/threat-intel/vulnerabil…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://plugins.trac.wordpress.org/browser/fusion…
https://avada.com/documentation/avada-changelog/

Impacted products

1 product

Vendor	Product	Version
themefusion	Avada (Fusion) Builder	Affected: 0 , ≤ 3.15.2 (semver)

Credits

Tin Pham Trong Pham Hao Ngo

Show details on NVD website

JSON

To clipboard

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        "metrics": [
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                "id": "CVE-2026-6279",
                "options": [
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                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
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                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-21T12:22:05.314059Z",
                "version": "2.0.3"
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        },
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    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Avada (Fusion) Builder",
          "vendor": "themefusion",
          "versions": [
            {
              "lessThanOrEqual": "3.15.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
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        {
          "lang": "en",
          "type": "finder",
          "value": "Tin Pham"
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          "lang": "en",
          "type": "finder",
          "value": "Trong Pham"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Hao Ngo"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The Avada Builder (fusion-builder) plugin for WordPress is vulnerable to Unauthenticated Remote Code Execution via PHP Function Injection in versions up to and including 3.15.2. This is due to the `wp_conditional_tags` case in `Fusion_Builder_Conditional_Render_Helper::get_value()` passing attacker-controlled values from a base64-decoded JSON blob directly to `call_user_func()` without any allowlist validation. This is exploitable by unauthenticated attackers through the `fusion_get_widget_markup` AJAX endpoint, which is registered for non-privileged (unauthenticated) users via `wp_ajax_nopriv_fusion_get_widget_markup`. The endpoint is protected only by a nonce (`fusion_load_nonce`), but this nonce is generated for user ID 0 and is deterministically exposed in the JavaScript output of any public-facing page containing a Post Cards (`[fusion_post_cards]`) or Table of Contents (`[fusion_table_of_contents]`) element. This makes it possible for unauthenticated attackers to execute arbitrary code on affected sites."
        }
      ],
      "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"
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      "providerMetadata": {
        "dateUpdated": "2026-05-21T04:27:57.613Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
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      },
      "references": [
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          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/5dc72d78-d47c-4b36-8d69-8672e15ddf8c?source=cve"
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          "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1531"
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          "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/shortcodes/fusion-widget.php#L44"
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        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/class-fusion-builder.php#L7551"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/class-fusion-builder.php#L7551"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/trunk/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1083"
        },
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          "url": "https://plugins.trac.wordpress.org/browser/fusion-builder/tags/3.15.0/inc/helpers/class-fusion-builder-conditional-render-helper.php#L1083"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.
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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.

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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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GHSA-F53P-382V-8PJ7

CVE-2026-6279 (GCVE-0-2026-6279)

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