WPMU DEV Forminator Forms Plugin up to 1.57.0 on WordPress error_description cross site scripting

Summaryinfo

A vulnerability, which was classified as problematic, was found in WPMU DEV Forminator Forms Plugin up to 1.57.0. Affected by this issue is some unknown functionality. The manipulation of the argument error_description results in cross site scripting. This vulnerability is identified as CVE-2026-18328. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in WPMU DEV Forminator Forms Plugin up to 1.57.0. Affected is some unknown functionality. The manipulation of the argument error_description with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. CVE summarizes:

The Forminator Forms – Contact Form, Payment Form & Custom Form Builder plugin for WordPress is vulnerable to DOM-Based Reflected Cross-Site Scripting via the 'error_description' parameter in all versions up to, and including, 1.57.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The vulnerability is only triggerable on pages hosting a Forminator form configured to use the Stripe Checkout Sessions payment API, which became the default in 1.56.0.

The advisory is shared for download at wordfence.com. This vulnerability is traded as CVE-2026-18328 since 07/29/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.007.

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

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-65316). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• WordPress Plugin

Vendor

• WPMU DEV

Name

• Forminator Forms Plugin

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31
• 1.32
• 1.33
• 1.34
• 1.35
• 1.36
• 1.37
• 1.38
• 1.39
• 1.40
• 1.41
• 1.42
• 1.43
• 1.44
• 1.45
• 1.46
• 1.47
• 1.48
• 1.49
• 1.50
• 1.51
• 1.52
• 1.53
• 1.54
• 1.55
• 1.56
• 1.57.0

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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