CVE-2024-13738 Overview
CVE-2024-13738 affects the Motors - Car Dealer, Rental & Listing WordPress theme developed by StyleMix Themes. The vulnerability allows unauthenticated attackers to execute arbitrary shortcodes through improper validation before a do_shortcode call. All versions up to and including 5.6.65 are affected. The flaw is classified under CWE-94: Improper Control of Generation of Code and carries a CVSS score of 7.3. Attackers can abuse this weakness over the network without authentication or user interaction, impacting site confidentiality, integrity, and availability.
Critical Impact
Unauthenticated attackers can trigger arbitrary WordPress shortcodes on vulnerable Motors theme installations, enabling content injection and abuse of plugin-provided shortcode functionality.
Affected Products
- Motors - Car Dealer, Rental & Listing WordPress theme by StyleMix Themes
- All versions up to and including 5.6.65
- WordPress installations using the Motors theme for automotive, dealership, or classifieds sites
Discovery Timeline
- 2025-05-03 - CVE-2024-13738 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-13738
Vulnerability Analysis
The Motors WordPress theme exposes a code injection weakness rooted in unsafe handling of user-supplied input prior to shortcode rendering. The theme calls the WordPress do_shortcode function on attacker-controlled values without enforcing validation or authorization checks. As a result, any remote actor can submit a crafted request that the theme parses and executes as a shortcode. Because shortcodes can invoke arbitrary registered handlers from the theme and any active plugins, the impact extends beyond the theme itself. Attackers can leverage shortcodes that render protected content, send emails, query the database, or interact with third-party integrations available on the target site.
Root Cause
The root cause is missing input validation on a parameter that flows into do_shortcode. WordPress treats do_shortcode output as trusted markup, so any value that reaches that function is parsed and dispatched to the matching shortcode handler. The theme accepts the value through an action accessible to unauthenticated users and does not constrain the allowed shortcode tags or attributes. This pattern maps to CWE-94, Improper Control of Generation of Code.
Attack Vector
Exploitation occurs over the network against the theme's exposed action endpoint. An attacker sends an HTTP request containing a shortcode string in the unvalidated parameter. The theme passes that string directly to do_shortcode, which renders it server-side using the privileges of the web application. No credentials, session, or user interaction are required. Refer to the Wordfence Vulnerability Analysis for additional technical context.
Detection Methods for CVE-2024-13738
Indicators of Compromise
- HTTP POST or GET requests to admin-ajax.php or theme-specific endpoints containing bracketed shortcode syntax such as [shortcode_name ...] in parameter values
- Unauthenticated requests originating from low-reputation IP addresses targeting Motors theme action handlers
- Unexpected outbound network traffic or email generation correlated with web request bursts to the affected site
- Web server log entries showing request parameters with shortcode tags belonging to installed plugins
Detection Strategies
- Inspect WordPress access logs for request parameters containing [ and ] bracket pairs paired with known shortcode names
- Deploy WAF rules that block unauthenticated requests carrying shortcode markup in body or query parameters
- Enumerate installed WordPress themes and confirm whether the Motors theme version is at or below 5.6.65
Monitoring Recommendations
- Enable verbose logging on the WordPress AJAX endpoint and review for anomalous parameter content
- Monitor for spikes in unauthenticated POST traffic to theme action handlers
- Alert on file modifications within the active theme directory and on new outbound SMTP or HTTP connections from the web host
How to Mitigate CVE-2024-13738
Immediate Actions Required
- Update the Motors theme to the latest available release from StyleMix Themes or ThemeForest
- Audit WordPress installations to identify sites running the Motors theme version 5.6.65 or earlier
- Review recent web server and application logs for evidence of shortcode injection attempts
Patch Information
The vendor changelog does not clearly identify the patched build, so administrators should install the most recent Motors theme release available from StyleMix Themes or ThemeForest. Validate the installed version after upgrading and confirm that the previously vulnerable action no longer processes unauthenticated shortcode input. Consult the Wordfence advisory for the latest remediation guidance.
Workarounds
- Restrict access to the vulnerable theme endpoint at the web server or WAF layer until patching is complete
- Disable the Motors theme and switch to a maintenance theme if an immediate update cannot be applied
- Remove or unregister non-essential shortcodes from active plugins to reduce the available attack surface
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
