WordPress security changelog
CRITICAL CVE-2026-15748 Deferred

Forminator public submissions permit unauthenticated executable file upload

Forminator Forms through 1.56.1 lets an unauthenticated attacker forge a Select field value so the public submission handler trusts attacker-controlled upload-field configuration. The handle_file_upload() dangerous-extension blocklist performs exact-key matching and can be bypassed with pipe-alternative MIME type keys, allowing files that may be executable to reach the upload operation and potentially produce remote code execution.

CVE / CNA score 9.8 CVSS 3.1 · security@wordfence.com
NVD score Pending NVD has not published its own CVSS assessment.
Component
Forminator Forms – Contact Form, Payment Form & Custom Form Builder
Plugin slug
forminator
Affected
<= 1.56.1
Safe version
> 1.56.1
Published
Aug 18, 2026
Weakness
CWE-434 — Unrestricted Upload of File with Dangerous Type

This CVE was published Aug 18, 2026 and is one of 47 known issues for this plugin.

What to do

Update, patch or deactivate.

Update Forminator Forms to a release after 1.56.1. Until a confirmed update is installed, disable public upload fields or deactivate the plugin when warranted by the site's risk profile. Review uploads and server files for unexpected executable content and investigate the site as potentially compromised if exploitation is suspected.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical description

The Forminator Forms plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 1.56.1 via the handle_file_upload function. This is due to insufficient file type validation in handle_file_upload, where the dangerous-extension blocklist performs exact-key matching that is bypassed by pipe-alternative MIME type keys, combined with a public submission handler that trusts attacker-controlled upload field configuration injected via a forged Select field value. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Primary and upstream sources