CVE-2026-13405 in Royal Addons Plugin
Summary
by MITRE • 08/20/2026
The Royal Addons for Elementor WordPress plugin before 1.7.1066 does not correctly sanitise custom widget markup before writing it to a file that is later executed, allowing users with the manage_options capability (and, on WordPress Multisite, non-super subsite administrators who do not otherwise hold code-execution capabilities) to execute arbitrary PHP code.
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Analysis
by VulDB Data Team • 08/20/2026
The vulnerability identified in Royal Addons for Elementor prior to version 1.7.1066 represents a critical server-side code injection flaw rooted in insufficient input validation and sanitization mechanisms. This specific weakness allows authenticated attackers with the manage_options capability, which is typically granted to administrators, to inject malicious PHP code into files that are subsequently executed by the WordPress environment. In multisite installations, this vulnerability extends its reach to non-super subsite administrators who lack other direct code-execution privileges, thereby expanding the attack surface significantly within a multi-tenant architecture. The core technical failure lies in how the plugin handles custom widget markup; rather than strictly validating or escaping user-supplied data before persisting it to disk, the application writes raw input directly into executable files without adequate filtering of dangerous characters or function calls.
From a classification perspective, this vulnerability aligns with CWE-94, which describes Improper Control of Generation of Code (Code Injection), and more specifically CWE-732 in contexts where permission constraints are bypassed to achieve unintended execution privileges. The operational impact is severe because it results in Remote Code Execution as the web server user or system-level equivalent depending on the hosting configuration. Once an attacker successfully injects PHP code into a file that is later included or required by the application, they gain full control over the underlying WordPress installation. This can lead to complete compromise of the website's data integrity, confidentiality, and availability. Attackers may use this access to deface the site, steal sensitive user information, install backdoors for persistent access, or pivot further into internal networks if the server is part of a larger infrastructure.
The exploitation path typically involves an authenticated administrator navigating to the plugin’s configuration interface where custom widgets can be defined. By injecting PHP code snippets disguised as legitimate widget parameters or markup attributes, the attacker ensures that when the system saves these settings and later renders them by including the generated file, the malicious payload executes automatically. This process bypasses standard WordPress security checks because the execution context is tied to the administrative actions permitted under manage_options rather than public-facing endpoints often targeted in cross-site scripting attacks. The presence of this flaw highlights a common pitfall in plugin development where dynamic content generation fails to adhere to strict separation between data and executable code, violating fundamental secure coding principles regarding input handling.
Mitigation strategies must prioritize immediate patching by upgrading the Royal Addons for Elementor plugin to version 1.7.1066 or later, which addresses these sanitization gaps. In environments where updating is not immediately feasible, administrators should restrict manage_options capabilities to only those users who absolutely require them, leveraging role management plugins to enforce least privilege principles. Additionally, implementing Web Application Firewall rules that detect and block common PHP injection patterns in POST requests targeting plugin settings pages can provide a layer of defense-in-depth. Monitoring server logs for unusual file creation events or unexpected includes within the wp-content directory associated with this plugin is also recommended to detect potential exploitation attempts early. Regular security audits focusing on input validation practices across all third-party plugins are essential to prevent similar vulnerabilities from being introduced in future updates, ensuring compliance with industry standards such as OWASP Top Ten guidelines regarding injection flaws and broken access control mechanisms aligned with MITRE ATT&CK techniques for initial access via compromised credentials or application exploits.