Ultra Addons for Contact Form 7 - Security Vulnerability (CVE-2026-84750)

Q: Am I affected by this vulnerability?

You are affected if your site runs Ultra Addons for Contact Form 7. Versions below 3.5.51 are vulnerable; that release and later are not. No account is needed to exploit this, so a public site is reachable by anyone.

Q: How do I fix it?

Update Ultra Addons for Contact Form 7 to version 3.5.51 or later. That is the complete fix. 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-2026-84750

Vulnerability CVE-2026-84750 PLUGIN ultra-addons-for-contact-form-7 MEDIUM

The Ultra Addons for Contact Form 7 WordPress plugin before 3.5.51 does not validate the type or extension of files uploaded through one of its form fields, and stores them at a predictable public path with the attacker-chosen extension intact, allowing unauthenticated users to upload arbitrary files. The PHP handler shipped by default with the Debian and Ubuntu Apache packages maps .phar to PHP alongside .php and .phtml, so on that stack the uploaded file is executed and the issue leads to Remote Code Execution and full site takeover. Where the host routes only .php to the PHP handler, the same file is instead served from the site's own origin with its script intact, leading to Stored Cross-Site Scripting.

CVE-2026-84750

MEDIUM CVSS 6.5 Published 2026-09-19 Updated 2026-09-21

AI Risk Elevated (70/100) Active Exploit: No strong signal Published Exploit: No public exploit references Priority: P3 Priority

Severity Band MEDIUM

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

Affected Components 1

Reference Links 1

AI Risk Engine Elevated (70/100)

Exploitability High

Active Exploitation No strong signal

Published Exploit Status No public exploit references

Threat Timeline

2026-09-19 CVE published and first recorded in the threat feed.
2026-09-21 Record updated with latest vulnerability metadata.
2026-09-26 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 47 days ago

AI enriched 47 days ago (2026-09-26 10:16 UTC)

Technical Summary

Potential Impact

Severity is MEDIUM (CVSS 6.5). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as 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 70/100 (Elevated, High) with priority P3 Priority. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.

Affected Products

Ultra Addons for Contact Form 7 PLUGIN · ultra-addons-for-contact-form-7 Affected: < 3.5.51 Fixed in: 3.5.51

References

https://wpscan.com/vulnerability/44f68354-4be3-422f-9f94-af980b2ebc44/

What to do about this

Patch promptly The consequence is significant even where an attacker needs a foothold first.

Fix it

Update Ultra Addons for Contact Form 7 to 3.5.51 or later.

That is the complete fix. Everything below is what protects you in the meantime.

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.

Compare Hack Halt plans Start free

Not sure if you are affected?

Scan your site to see whether it runs Ultra Addons for Contact Form 7, and at which version.

Free, no installation, no account. It reads what your site already publishes, then tells you which plugins carry known vulnerabilities and what to do about each one.

Scan my site free See what Hack Halt does

Am I affected by this vulnerability?