CVE-2026-103039 (GCVE-0-2026-103039)

Vulnerability from cvelistv5 – Published: 2026-10-30 06:47 – Updated: 2026-10-30 15:57
VLAI
Title
Gravity Forms <= 3.1.2 - Unauthenticated PHP Object Injection via Post Custom Field
Summary
The Gravity Forms plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.1.2 via a Post Custom Field whose input type is List. This is due to GFFormsModel::create_post() passing the submitted value to WordPress' unrestricted global maybe_unserialize() rather than the plugin's own hardened GFCommon::maybe_unserialize(), which was added in 3.1.1 and passes allowed_classes => false precisely to prevent object instantiation. Where the field has a content template enabled, the submitted row reaches that call verbatim. This makes it possible for unauthenticated attackers to inject a PHP object into post meta. No PHP Object Injection gadget chain is present in the plugin itself; however, if a gadget chain is present via an additional plugin or theme, it could allow the attacker to perform actions such as remote code execution. Where the custom field is mapped to the protected _wp_page_template meta key, WordPress itself supplies the chain: validate_file() accepts non-scalars, WP_Theme::__toString() then resolves an attacker-controlled path, and on hosts with a readable PEAR install and register_argc_argv enabled this yields remote code execution.
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 2026-10-30 15:48 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2391 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Gravity Forms Gravity Forms Affected: 0 , ≤ 3.1.2 (semver)
guessed Create a notification for this product.
Credits
Tin Pham (TF1T) Hao Ngo Trong Pham
Show details on NVD website
To clipboard 

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