Vulnerability · Published Oct 25, 2021 · Assigned by WPScan
CVE-2021-24884Formidable Form Builder < 4.09.05 - Unauthenticated Stored Cross-Site Scripting
Critical 9.6
In plain English
A critical-severity cross-site scripting in Formidable Form Builder – Contact Form, Survey & Quiz Forms Plugin for WordPress from Unknown. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 3.1% (higher than 88% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Unknown | Formidable Form Builder – Contact Form, Survey & Quiz Forms Plugin for WordPress | 4.09.05 – before 4.09.05 |
Weakness: CWE-79