CVE-2021-24884

Public Exploit
Formidable Form Builder < 4.09.05 - Unauthenticated Stored Cross-Site Scripting

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.

Category

9.6
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 19.16% Top 5%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory wpscan.com
Affected: Unknown Formidable Form Builder – Contact Form, Survey & Quiz Forms Plugin for WordPress
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-24884?
CVE-2021-24884 has been scored as a critical severity vulnerability.
How to fix CVE-2021-24884?
To fix CVE-2021-24884, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-24884 being actively exploited in the wild?
It is possible that CVE-2021-24884 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~19% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-24884?
CVE-2021-24884 affects Unknown Formidable Form Builder – Contact Form, Survey & Quiz Forms Plugin for WordPress.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.