CVE-2026-89435 (GCVE-0-2026-89435)

Vulnerability from cvelistv5 – Published: 2026-10-30 06:47 – Updated: 2026-10-30 18:09
VLAI
Title
Formidable Forms <= 6.35 - Authenticated (Subscriber+) Arbitrary Plugin Installation via 'file_url' Parameter
Summary
The Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More plugin for WordPress is vulnerable to Arbitrary Plugin Installation in all versions up to, and including, 6.35 via the 'file_url' parameter parameter. This is due to insufficient URL prefix validation in validate_url_is_in_s3_bucket() and a permission callback that relies solely on a shared token obtainable by any user with the delegable frm_view_forms capability, without checking install_plugins or activate_plugins capabilities. This makes it possible for authenticated attackers, with subscriber-level access and above, to install arbitrary plugins on the server. Exploitation additionally requires that the site is free-only (Formidable Pro is NOT installed).
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-30 17:32 UTC
CWE
  • CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2401 records in the last 180 days details
References
Impacted products
Credits
Supakiad S. (m3ez)
Show details on NVD website
To clipboard 

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