Arbitrary file upload in Ultra Addons For Contact Form 7

CVE-2026-84750

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.

Vulnerability class: Unrestricted File Upload

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

Affected products

  • Unknown Ultra Addons For Contact Form 7

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-84750?
CVE-2026-84750 is a medium-severity vulnerability in Ultra Addons For Contact Form 7, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 6.5/10. Published 2026-09-19.
How severe is CVE-2026-84750?
Medium severity. CVSS v3 base score is 6.5 out of 10.