CVE-2026-8809

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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Advanced Custom Fields: Extended", "vendor": "hwk-fr", "versions": [{"lessThanOrEqual": "0.9.2.5", "status": "affected", "version": "0", "versionType": "semver"}]}], "source": "security@wordfence.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "The Advanced Custom Fields: Extended plugin for WordPress is vulnerable to Privilege Escalation via Validation Bypass in all versions up to and including 0.9.2.5. The vulnerability exists due to the after_validate_save_post() function unconditionally trusting the attacker-controlled _acf_post_id POST parameter \u2014 with no authentication or integrity verification \u2014 to select a cleanup branch that silently discards all validation errors not prefixed with acfe:. This makes it possible for unauthenticated attackers to suppress both the role allow-list validation error added by acfe_field_user_roles::validate_front_value() and the administrator-role capability guard error added by acfe_module_form_action_user::validate_action(), causing wp_insert_user() to execute with an attacker-supplied administrator role argument and resulting in the creation of a new administrator-level user account. Exploitation requires the target site to expose a public ACFE frontend form configured with a Create User action that maps a role field."}, {"lang": "es", "value": "El plugin Advanced Custom Fields: Extended para WordPress es vulnerable a escalada de privilegios a trav\u00e9s de un bypass de validaci\u00f3n en todas las versiones hasta la 0.9.2.5 inclusive. La vulnerabilidad existe debido a que la funci\u00f3n after_validate_save_post() conf\u00eda incondicionalmente en el par\u00e1metro POST _acf_post_id controlado por el atacante \u2014 sin autenticaci\u00f3n ni verificaci\u00f3n de integridad \u2014 para seleccionar una rama de limpieza que descarta silenciosamente todos los errores de validaci\u00f3n no prefijados con acfe:. Esto hace posible que atacantes no autenticados supriman tanto el error de validaci\u00f3n de la lista de permitidos de roles a\u00f1adido por acfe_field_user_roles::validate_front_value() como el error de protecci\u00f3n de capacidad de rol de administrador a\u00f1adido por acfe_module_form_action_user::validate_action(), haciendo que wp_insert_user() se ejecute con un argumento de rol de administrador proporcionado por el atacante y resultando en la creaci\u00f3n de una nueva cuenta de usuario de nivel de administrador. La explotaci\u00f3n requiere que el sitio objetivo exponga un formulario frontend p\u00fablico de ACFE configurado con una acci\u00f3n de Crear Usuario que mapee un campo de rol."}], "id": "CVE-2026-8809", "lastModified": "2026-07-21T10:10:00.103", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "security@wordfence.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-8809", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-05-29T10:03:00.555711Z", "version": "2.0.3"}}]}, "published": "2026-05-28T23:16:44.760", "references": [{"source": "security@wordfence.com", "url": "https://plugins.trac.wordpress.org/browser/acf-extended/tags/0.9.2.4/includes/hooks.php#L636"}, {"source": "security@wordfence.com", "url": "https://plugins.trac.wordpress.org/browser/acf-extended/tags/0.9.2.4/includes/module-acf.php#L141"}, {"source": "security@wordfence.com", "url": "https://plugins.trac.wordpress.org/browser/acf-extended/tags/0.9.2.4/includes/modules/form/module-form-action-user.php#L715"}, {"source": "security@wordfence.com", "url": "https://plugins.trac.wordpress.org/browser/acf-extended/tags/0.9.2.4/includes/modules/form/module-form-front.php#L94"}, {"source": "security@wordfence.com", "url": "https://plugins.trac.wordpress.org/changeset/3551665/acf-extended"}, {"source": "security@wordfence.com", "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/bd332f49-5aa9-4207-89db-84692a6430e0?source=cve"}], "sourceIdentifier": "security@wordfence.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-269"}], "source": "security@wordfence.com", "type": "Secondary"}]}

{}

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