Sigma Forms Pro <= 1.4.5 - Unauthenticated Unauthenticated Arbitrary File Upload Leading to Remote Code Execution via Pre-built Template File Upload Field
Strategic Overview
- Status
- Patched in 1.4.6
- Affected Plugin
- SigmaForms Pro – AI Generated Forms
- Affected Version
<= 1.4.5- CVSS
- 9.8Critical
- Weakness type
- CWE-434 · Unrestricted Upload of File with Dangerous Type
- CVE
CVE-2026-14494
At a glance
CVE-2026-14494 is a critical-severity Unrestricted Upload of File with Dangerous Type vulnerability in the SigmaForms Pro WordPress plugin, affecting versions <= 1.4.5. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 1.4.6; sites on affected versions should update now. Disclosed August 2026, reported by d.v4n_s3c.
Vulnerability Overview
The Sigma Forms Pro plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 1.4.5 via the handle_form_submission function. This is due to the plugin dynamically granting the unfiltered_upload capability to all users during form submissions and bypassing MIME type validation when allowed_file_types is not configured. This makes it possible for unauthenticated attackers to execute code on the server. Several default pre-built templates including Job Application, Support Ticket, and Wholesale Application have file upload fields with no file type restrictions configured by design, making this vulnerability immediately exploitable upon installation.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.
CWE-434: Unrestricted Upload of File with Dangerous Type
Reaching this weakness in SigmaForms Pro <= 1.4.5 takes no account at all. An unrestricted file upload lets a caller store a file whose type or destination the application does not properly constrain.
If an uploaded file lands anywhere the server will execute, the flaw becomes remote code execution and the site should be treated as fully compromised. For SigmaForms Pro the fix is 1.4.6: builds <= 1.4.5 are affected, anything from 1.4.6 onward is not.
Remediation
Update to version 1.4.6, or a newer patched version
How does WordSec protect against this?
Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. Classes like this one can leave something behind, so the staged malware scanner is the second half: it looks for dropped files and modified code rather than for the request that created them. None of that substitutes for the fix: SigmaForms Pro 1.4.6 closes this, and updating the plugin is the step that ends it.
- Firewall
- Scanner
- Login Security
External References
Related records
Other vulnerabilities in SigmaForms Pro – AI Generated Forms
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