CVE-2026-4883
Piotnet Forms <= 2.1.40 - Unauthenticated Arbitrary File Upload via Form File Upload
- State
- Published
- Severity
- 9.8 Critical
- Published
- May 19, 2026
- Updated
- May 19, 2026
- Reserved
- Mar 26, 2026
Description
The Piotnet Forms plugin for WordPress is vulnerable to arbitrary file upload due to missing file type validation in the 'piotnetforms_ajax_form_builder' function in all versions up to, and including, 2.1.40. The plugin uses an incomplete extension blacklist that only blocks php, phpt, php5, php7, and exe extensions, while allowing dangerous extensions such as .phar or .phtml to be uploaded. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible. Note: The exploit can only be exploited if a file field is added to the form.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | Wordfence |
Weaknesses
- CWE-434 Unrestricted Upload of File with Dangerous Type
Affected Products
| Product | Versions |
|---|---|
Piotnet FormsPiotnet |
|
References
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