Is CVE-2021-24884 actively exploited?

No active exploitation of CVE-2021-24884 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-24884 be exploited remotely?

Yes. CVE-2021-24884 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-24884?

CVE-2021-24884 has a CVSS score of 9.6 (CRITICAL).

HOME VULNERABILITIESCVE-2021-24884

CRITICAL

CVE-2021-24884

CWE-79Published: October 25, 2021· Updated: Jun 17, 2026

9.6

CVSS v3.1

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.

NVD Source

Technical Analysis

CVE-2021-24884 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.6.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.