CVE-2026-54814: StylemixThemes Motors PHP File Inclusion RCE Vulnerability

Technical summary

CVE-2026-54814 is a PHP Remote File Inclusion (RFI) / Local File Inclusion (LFI) vulnerability cataloged under CWE-98 (Improper Control of Filename for Include/Require Statement in PHP Program). The Motors plugin versions up to and including 1.4.109 fail to properly sanitize or validate filenames passed to PHP include or require statements. This allows an attacker to manipulate the file path parameter to load arbitrary local files or, in certain configurations, remote files from an attacker-controlled server. Successful exploitation results in arbitrary PHP code execution with the privileges of the web server process.

Business impact

Compromise of a StylemixThemes Motors installation can lead to unauthorized access to sensitive data, modification of website content, injection of malware, and use of the compromised server as a pivot point for lateral movement within the organization's network. If Motors is used in a customer-facing or e-commerce context, this vulnerability could expose user data, payment information, and damage customer trust. The ability to execute arbitrary code means attackers can install persistent backdoors, making remediation complex and time-consuming.

Affected systems

StylemixThemes Motors versions 1.4.109 and earlier are affected. Verify your current Motors version through the plugin settings or by inspecting the plugin directory. Environments running WordPress with the Motors plugin installed are at risk, particularly if the plugin is exposed to untrusted input or if file upload functionality is enabled without proper restrictions.

Exploitability

While the vulnerability requires somewhat difficult conditions to exploit (CVSS Attack Complexity: High), it does not require authentication or user interaction. An attacker with network access to the vulnerable server can craft a request to exploit the file inclusion flaw. The practical exploit path depends on the specific Motors version, the web server configuration, and what files are accessible or writable on the system. Organizations should assume this vulnerability is exploitable in real-world scenarios, especially if the plugin receives direct internet exposure.

Remediation

Update StylemixThemes Motors to a version newer than 1.4.109 as soon as patches become available. Verify the update through the vendor's official channels. In the interim, restrict network access to the affected WordPress installation, disable the Motors plugin if it is not in active use, and implement Web Application Firewall (WAF) rules to block common file inclusion attack patterns. Review server logs for signs of exploitation attempts targeting file inclusion parameters.

Patch guidance

Check the StylemixThemes website or the Motors plugin repository for available updates beyond version 1.4.109. Apply patches during a maintenance window after backing up your WordPress installation and database. Test the patched version in a staging environment to ensure compatibility with other plugins and your site configuration. After deployment, verify that the patch version number is correctly reflected in the plugin details.

Detection guidance

Monitor web server logs and WordPress audit logs for requests containing suspicious file path parameters, such as those with ../ sequences, file:// or php:// wrappers, or references to sensitive files (e.g., /etc/passwd). Intrusion detection systems should flag attempts to abuse include/require statements. Review access patterns to the Motors plugin's main PHP files, particularly looking for requests with unusual or encoded query strings. Check for unexpected file creation or modification in the WordPress directory.

Why prioritize this

This vulnerability merits urgent attention because it allows unauthenticated remote code execution on the web server, despite the moderately complex attack conditions. The combination of HIGH CVSS severity (8.1), the ability to execute arbitrary PHP, and the absence of a KEV listing (suggesting it may not yet be widely exploited in the wild) creates a narrow window for defensive action. Organizations running Motors should treat this as a critical security incident waiting to happen.

Risk score, explained

The CVSS 3.1 score of 8.1 (HIGH severity) reflects the impact of successful exploitation: high confidentiality loss (sensitive files can be read), high integrity loss (files can be modified or backdoors installed), and high availability loss (the server can be taken offline or consumed by malicious processes). The Attack Complexity is rated High because the attacker must understand the file structure and have specific knowledge of the target environment, but the lack of authentication or user interaction requirements keeps the overall score elevated.

Frequently asked questions