CVE-2023-45748

MailChimp Forms by MailMunch <= 3.1.7 - Cross-Site Request Forgery via Multiple AJAX actions

2023-10-12 00:00
Abdi Pranata

Strategic Overview

Status
Patched in 3.1.8
Affected Plugin
Mailmunch Forms for Mailchimp
Affected Version
<= 3.1.7
CVSS
5.4Medium
Weakness type
CWE-352 · Cross-Site Request Forgery (CSRF)
CVE
CVE-2023-45748
View all Mailmunch Forms for Mailchimp vulnerabilities

At a glance

CVE-2023-45748 is a medium-severity Cross-Site Request Forgery (CSRF) vulnerability in the Mailmunch Forms for Mailchimp WordPress plugin, affecting versions <= 3.1.7. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 3.1.8; sites on affected versions should update now. Disclosed October 2023, reported by Abdi Pranata.

Vulnerability Overview

The MailChimp Forms by MailMunch plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 3.1.7. This is due to missing nonce validation on several of the plugin's functions, such as delete_email(), delete_widget(), change_email_status(), and settings_page(). This makes it possible for unauthenticated attackers to delete widgets and change or delete arbitrary email subscriber records via a forged request granted they can trick a site administrator 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-352: Cross-Site Request Forgery (CSRF)

Mailmunch Forms for Mailchimp <= 3.1.7 carries this weakness at delete_email(), and reaching it takes a caller who can reach the endpoint. Cross-site request forgery abuses the fact that browsers attach a victim's cookies to any request, so a state-changing action that only checks who you are, not whether you meant to act, can be triggered from another site.

An attacker who gets a logged-in user to load a crafted page can perform that action as them, with the impact scaling to whatever the victim's role is allowed to do. For Mailmunch Forms for Mailchimp the fix is 3.1.8: builds <= 3.1.7 are affected, anything from 3.1.8 onward is not.

Remediation

Update to version 3.1.8, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Mailmunch Forms for Mailchimp: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Mailmunch Forms for Mailchimp 3.1.8 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2023-45748https://www.wordfence.com/threat-intel/vulnerabilities/id/f4f96877-406b-4ec0-ac6b-ee1ffdb436e5https://nvd.nist.gov/vuln/detail/CVE-2023-45748

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C