WordPress security changelog
CRITICAL CVE-2021-24884 Modified

Formidable Form Builder: Code execution

Formidable Form Builder is affected by code execution. The vulnerable path is reachable without authentication. Successful exploitation can run attacker-controlled code in the WordPress hosting account.

CVE / CNA score Pending The CVE record has not published a CNA CVSS assessment.
NVD score 9.6 CVSS 3.1 · nvd@nist.gov
Component
Formidable Form Builder
Plugin slug
formidable-form-builder
Affected
See vendor advisory
Safe version
See mitigation notes
Published
Oct 25, 2021
Weakness
CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-352 — Cross-Site Request Forgery (CSRF)

This CVE was published Oct 25, 2021 and is one of 6 known issues for this plugin.

Update, patch or deactivate.

No fixed release is identified. Update Formidable Form Builder when a confirmed fixed release becomes available; until then, disable and remove it when the site's risk warrants.

No confirmed safe version is listed. Consider a vendor-supported patch or temporarily restricting the affected functionality while you assess the risk.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Technical description

The Formidable Form Builder WordPress plugin before 4.09.05 allows to inject certain HTML Tags like <audio>,<video>,<img>,<a> and<button>.This could allow an unauthenticated, remote attacker to exploit a HTML-injection byinjecting a malicous link. The HTML-injection may trick authenticated users to follow the link. If the Link gets clicked, Javascript code can be executed. The vulnerability is due to insufficient sanitization of the "data-frmverify" tag for links in the web-based entry inspection page of affected systems. A successful exploitation incomibantion with CSRF could allow the attacker to perform arbitrary actions on an affected system with the privileges of the user. These actions include stealing the users account by changing their password or allowing attackers to submit their own code through an authenticated user resulting in Remote Code Execution. If an authenticated user who is able to edit Wordpress PHP Code in any kind, clicks the malicious link, PHP code can be edited.

NVD vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Primary and upstream sources