CVE-2024-3866: kstover ninja forms – the contact form builder that grows with you Cross-site Scripting

Vulnerability summary

CVE-2024-3866 is a medium (CVSS 6.1) Cross-site Scripting vulnerability in kstover ninja forms – the contact form builder that grows with you. EPSS estimates a 0.29% chance of exploitation in the next 30 days, higher than 20.3% of scored vulnerabilities.

Timeline

1. 25-09-2024
   PublishedVulnerability first disclosed.
2. 08-04-2026
   Last modifiedVulnerability information updated.

Description

The Ninja Forms Contact Form plugin for WordPress is vulnerable to Reflected Self-Based Cross-Site Scripting via the 'Referer' header in all versions up to, and including, 3.8.15 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. Successful exploitation of this vulnerability requires "maintenance mode" for a targeted form to be enabled. However, there is no setting available to the attacker or even an administrator-level user to enable this mode. The mode is only enabled during a required update, which is a very short window of time. Additionally, because of the self-based nature of this vulnerability, attackers would have to rely on additional techniques to execute a supplied payload in the context of targeted user.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.