Simple Form - Security Vulnerability (CVE-2026-118235)

Q: Am I affected by this vulnerability?

You are affected if your site runs Simple Form. No account is needed to exploit this, so a public site is reachable by anyone.

Q: How do I fix it?

Update Simple Form to the latest available version. Where the vendor has not yet published a fix, remove or disable the plugin until they do. Until you can update, Request / payload inspection (WAF) in Hack Halt ProSecure contains this class of attack at the request layer.

Q: What can an attacker actually do?

This is a Remote Code Execution flaw. An attacker who exploits it can run their own code on the server, which is total control of the site.

CVE-2026-118235

Vulnerability CVE-2026-118235 PLUGIN simple-form CRITICAL

The SimpleForm – Form Maker to Chat Apps with Quiz, Poll and Multi Lead Notifications plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 3.10.2 via the handle_upload function. This is due to missing server-side file key allowlist and pre-sanitization extension derivation that allows a trailing-dot filename to bypass all extension and MIME validation in handle_upload. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible. The only access control is a nonce that is printed into every public form's data-nonce attribute, making it trivially obtainable by any unauthenticated visitor on a page embedding the form shortcode.

CVE-2026-118235

CRITICAL CVSS 9.8 Published 2026-10-31 Updated 2026-11-02

AI Risk Critical (100/100) Active Exploit: No strong signal Published Exploit: No public exploit references Priority: P1 Immediate

Severity Band CRITICAL

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

Affected Components 2

Reference Links 9

AI Risk Engine Critical (100/100)

Exploitability Very High

Active Exploitation No strong signal

Published Exploit Status No public exploit references

Threat Timeline

2026-10-31 CVE published and first recorded in the threat feed.
2026-11-02 Record updated with latest vulnerability metadata.
2026-11-07 AI technical context refreshed for mitigation and impact guidance.
Now Monitoring for follow-up changes, linked references, and new related CVEs.

AI Context

Machine-generated threat intelligence

AI Updated 4 days ago

AI enriched 4 days ago (2026-11-07 18:45 UTC)

Technical Summary

Potential Impact

Severity is CRITICAL (CVSS 9.8). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as Very High based on remote code execution potential, low-bar exploit prerequisites.

Primary risk drivers: remote code execution potential, low-bar exploit prerequisites

Mitigation Recommendations

Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.

Detection & Monitoring

Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.

Business Impact Lens

AI risk score 100/100 (Critical, Very High) with priority P1 Immediate. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.

Affected Products

Simple Form PLUGIN · simple-form Affected: <= 3.10.2 Fixed version not specified

SimpleForm PLUGIN · simpleform Affected: <= 3.10.2 Fixed version not specified

References

What to do about this

Patch immediately Serious, and reachable without meaningful privilege.

Fix it

Update Simple Form to the latest available version.

Where the vendor has not published a fix yet, disable the plugin until they do.

Cannot update today? Request / payload inspection (WAF) in Hack Halt ProSecure blocks this class of attack before WordPress processes the request.

Inspect request parameters and bodies for injection, traversal and file-inclusion payloads, and refuse the request rather than logging it.

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Not sure if you are affected?

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