CVE-2026-39515 Overview
CVE-2026-39515 is a broken access control vulnerability in the Motors Car Dealership & Classified Listings plugin for WordPress. The flaw affects plugin versions prior to 1.4.107. Authenticated users with Subscriber-level privileges can perform actions reserved for higher-privileged roles. The weakness is classified under CWE-862: Missing Authorization. The vulnerability impacts availability of the affected WordPress site but does not directly expose confidentiality or integrity. Site owners running the Motors plugin should upgrade to version 1.4.107 or later.
Critical Impact
Authenticated subscribers can trigger actions that disrupt site availability through missing authorization checks in the Motors plugin.
Affected Products
- WordPress Motors Car Dealership & Classified Listings plugin versions prior to 1.4.107
- WordPress sites that allow user registration at the Subscriber role
- Any WordPress deployment where the vulnerable plugin remains active
Discovery Timeline
- 2026-06-15 - CVE-2026-39515 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2026-39515
Vulnerability Analysis
The Motors plugin exposes one or more actions that lack proper capability or authorization verification. A WordPress user authenticated as a Subscriber, the lowest standard privilege role, can invoke these actions and trigger outcomes that affect site availability. Because the issue is rooted in missing authorization rather than authentication, any account that can log in to the site is sufficient to reach the vulnerable code path.
The vulnerability is reachable over the network and requires low attack complexity. No user interaction is required beyond the attacker logging in. The Patchstack advisory tracks this as a Subscriber-level broken access control issue limited to availability impact.
Root Cause
The root cause is CWE-862: Missing Authorization. One or more plugin endpoints — typically registered through admin-ajax.php, REST routes, or admin-post.php handlers — do not enforce a current_user_can() capability check or equivalent role validation. As a result, low-privilege authenticated users can call functionality intended for administrators or editors.
Attack Vector
An attacker first obtains or registers a Subscriber account on the target WordPress site. The attacker then sends an authenticated HTTP request to the vulnerable plugin endpoint. Because the handler omits authorization checks, the request executes and disrupts site availability. No synthetic exploit code is published here; refer to the Patchstack advisory for technical details.
Detection Methods for CVE-2026-39515
Indicators of Compromise
- Unexpected POST requests from Subscriber accounts to wp-admin/admin-ajax.php or Motors plugin REST routes
- Sudden availability degradation, missing listings, or modified plugin state following Subscriber activity
- Newly registered Subscriber accounts followed shortly by privileged plugin actions
Detection Strategies
- Review WordPress access logs for authenticated requests targeting Motors plugin endpoints originating from non-administrative roles
- Enable a WordPress audit logging plugin to record role-based action attempts and capability check failures
- Correlate Subscriber session activity with plugin configuration or data changes during the affected window
Monitoring Recommendations
- Alert on spikes in admin-ajax.php traffic with Motors-specific action parameters
- Monitor the installed plugin version and flag any site running Motors below 1.4.107
- Track creation of new low-privilege accounts followed by access to administrative URLs
How to Mitigate CVE-2026-39515
Immediate Actions Required
- Upgrade the Motors Car Dealership & Classified Listings plugin to version 1.4.107 or later
- Audit existing Subscriber accounts and remove any that are unrecognized or inactive
- Temporarily disable open user registration if Subscriber accounts are not required
Patch Information
The vendor addressed the issue in Motors plugin version 1.4.107. Apply the update through the WordPress plugin manager or by replacing the plugin files manually. Validate the installed version after the upgrade to confirm remediation. See the Patchstack advisory for full patch details.
Workarounds
- Restrict access to the plugin's AJAX and REST endpoints at the web server or WAF layer until patching
- Disable the Motors plugin if it is not actively in use on the site
- Set users_can_register to false in WordPress general settings to prevent new Subscriber account creation
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
