CVE-2026-103039
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.5% in the next 30 days (EPSS).
- Severity: 9.8 CRITICAL (CVSS).
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 0.5% · EPSS, next 30 days
- Weakness
- CWE-502 · Unsafe deserialization
- Record status
- Deferred
Attack profile CVSS 3.1 · 9.8
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-103039.md and follow it. Check whether this project is affected by CVE-2026-103039. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
