CVE-2024-8850

MC4WP: Mailchimp for WordPress 4.9.9 - 4.9.16 - Reflected Cross-Site Scripting

2024-09-18 00:00
kauenavarro

Strategic Overview

Status
Patched in 4.9.17
Affected Plugin
MC4WP: Mailchimp for WordPress
Affected Version
4.9.9 – 4.9.16
CVSS
6.1Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2024-8850
View all MC4WP: Mailchimp for WordPress vulnerabilities

At a glance

CVE-2024-8850 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the MC4WP WordPress plugin, affecting versions 4.9.9 – 4.9.16. It carries a CVSS score of 6.1 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 4.9.17; sites on affected versions should update now. Disclosed September 2024, reported by kauenavarro.

Vulnerability Overview

The MC4WP: Mailchimp for WordPress plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'email' parameter when a placeholder such as {email} is used for the field in versions 4.9.9 to 4.9.16 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.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

MC4WP 4.9.9 – 4.9.16 carries this weakness at email, and reaching it takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For MC4WP the fix is 4.9.17: builds 4.9.9 – 4.9.16 are affected, anything from 4.9.17 onward is not.

Remediation

Update to version 4.9.17, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to MC4WP: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: MC4WP 4.9.17 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2024-8850https://www.wordfence.com/threat-intel/vulnerabilities/id/1d2ba8ea-a75f-4069-b67d-f832acb1deefhttps://nvd.nist.gov/vuln/detail/CVE-2024-8850

Related records

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