Wpmet MetForm Pro Plugin up to 3.9.7 on WordPress Form Submission mf-calculation input validation

Summaryinfo

A vulnerability, which was classified as critical, was found in Wpmet MetForm Pro Plugin up to 3.9.7 on WordPress. This impacts an unknown function of the component Form Submission Handler. Such manipulation of the argument mf-calculation leads to input validation. This vulnerability is traded as CVE-2026-1782. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Wpmet MetForm Pro Plugin up to 3.9.7 on WordPress and classified as critical. Affected by this issue is some unknown functionality of the component Form Submission Handler. The manipulation of the argument mf-calculation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is confidentiality, integrity, and availability. CVE summarizes:

The MetForm Pro plugin for WordPress is vulnerable to Improper Input Validation in all versions up to, and including, 3.9.7 This is due to the payment integrations (Stripe/PayPal) trusting a user-submitted calculation field value without recomputing or validating it against the configured form price. This makes it possible for unauthenticated attackers to manipulate the payment amount via the 'mf-calculation' field in the form submission REST request granted there exists a specific form with this particular configuration.

The weakness was shared by Andrea Bocchetti. The advisory is available at wordfence.com. This vulnerability is handled as CVE-2026-1782 since 02/02/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 04/15/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• WordPress Plugin

Vendor

• Wpmet

Name

• MetForm Pro Plugin

Version

• 3.9.0
• 3.9.1
• 3.9.2
• 3.9.3
• 3.9.4
• 3.9.5
• 3.9.6
• 3.9.7

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Threat Intelligenceinfo

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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