CVE-2021-24163

Name: CVE-2021-24163
Creator: NVD / NIST
Published: 2021-04-05T19:15:15.31+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 1.44%

Last modified Jun 17, 2026

CVE-2021-24163 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. The AJAX action, wp_ajax_ninja_forms_sendwp_remote_install_handler, did not have a capability check on it, nor did it have any nonce protection, therefore making it possible for low-level users, such as subscribers, to install and activate the SendWP Ninja Forms Contact Form – The Drag and Drop Form Builder for WordPress WordPress plugin before 3.4.34 and retrieve the client_secret key needed to establish the SendWP connection while also installing the SendWP plugin.. EPSS estimates a 1.44% chance of exploitation in the next 30 days.

Description

The AJAX action, wp_ajax_ninja_forms_sendwp_remote_install_handler, did not have a capability check on it, nor did it have any nonce protection, therefore making it possible for low-level users, such as subscribers, to install and activate the SendWP Ninja Forms Contact Form – The Drag and Drop Form Builder for WordPress WordPress plugin before 3.4.34 and retrieve the client_secret key needed to establish the SendWP connection while also installing the SendWP plugin.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.44%

69.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Ninjaforms	Ninja Forms	< 3.4.34

References

https://wpscan.com/vulnerability/55fde9fa-f6cd-4546-bee8-4acc628251c2Exploit, Third Party Advisory
https://www.wordfence.com/blog/2021/02/one-million-sites-affected-four-severe-vulnerabilities-patched-in-ninja-forms/Third Party Advisory
https://wpscan.com/vulnerability/55fde9fa-f6cd-4546-bee8-4acc628251c2Exploit, Third Party Advisory
https://www.wordfence.com/blog/2021/02/one-million-sites-affected-four-severe-vulnerabilities-patched-in-ninja-forms/Third Party Advisory

Timeline

Published: Apr 5, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-24163?

How severe is CVE-2021-24163?

CVE-2021-24163 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 1.44% probability of exploitation in the next 30 days.

How do I fix CVE-2021-24163?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-24163?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST