by Kastro
Paper/Archive/CVE-2026-4883

CVE-2026-4883

Piotnet Piotnet Forms — Piotnet Forms <= 2.1.40 - Unauthenticated Arbitrary File Upload via Form File Upload

EPSS 3%CVSS 9.8
critical.is priorityof 100
47
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 87.6.876 × 2017.5No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
Piotnet Forms≤ 2.1.40–CNA

Scores by source

Wordfence (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refwordfence.com/threat-intel/vulnerabilities/id/9bd9c9db-d279-4de2-b5e4-ac7d8c919f2a?source=cverefpiotnetforms.com