Formidable Form Builder <= 4.09.04 - Unauthenticated Stored Cross-Site Scripting

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE CVE-2021-24884
CVSS Critical (9.6)
Publicly Published January 28, 2021
Last Updated January 22, 2024
Researcher Maximilian Barz
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.

References

1 affected software package

Software Type Plugin
Software Slug formidable (view on wordpress.org)
Patched? Yes
Affected Version
  • <= 4.09.05
Patched Version
  • 4.09.05
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