CVE-2015-9477 in Vernissage Theme
Summary
by MITRE
The Vernissage theme 1.2.8 for WordPress has insufficient restrictions on option updates.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 01/07/2024
The vulnerability identified as CVE-2015-9477 affects the Vernissage theme version 1.2.8 for WordPress platforms, representing a critical security flaw in the theme's option update mechanism. This vulnerability stems from inadequate access controls and validation procedures within the theme's administrative interfaces, creating potential pathways for unauthorized modifications to WordPress site configurations. The flaw specifically targets the theme's ability to process and validate user inputs during option update operations, which are typically restricted to authorized administrators.
The technical implementation of this vulnerability lies in the theme's failure to properly authenticate and authorize users attempting to modify theme options through WordPress's administrative dashboard. When users submit updates to theme settings, the system should verify that the requesting user possesses appropriate administrative privileges before processing these changes. However, the Vernissage theme 1.2.8 fails to implement robust validation checks, allowing malicious actors or compromised users with lower privileges to potentially manipulate theme configurations. This weakness directly corresponds to CWE-285, which addresses insufficient authorization in software systems, and aligns with ATT&CK technique T1068, which covers local privilege escalation through exploitation of application vulnerabilities.
The operational impact of this vulnerability extends beyond simple configuration modifications, as theme options often control critical aspects of website functionality including layout parameters, color schemes, and feature toggles that can indirectly affect site performance and security posture. An attacker exploiting this vulnerability could potentially disable security features, modify visual elements to facilitate phishing attacks, or alter theme behavior to redirect traffic to malicious destinations. The implications are particularly severe in multi-user WordPress environments where different roles have distinct permission levels, as the vulnerability could enable privilege escalation from subscriber or contributor roles to administrator status. This weakness creates opportunities for persistent threats to establish footholds within WordPress installations and maintain long-term access to compromised systems.
Mitigation strategies for CVE-2015-9477 should prioritize immediate theme updates to versions that address the authorization flaw, as the original vulnerable version 1.2.8 no longer receives security patches. System administrators should implement comprehensive monitoring of theme option changes through WordPress's built-in logging capabilities and third-party security plugins that can detect anomalous administrative activities. Additionally, organizations should enforce strict role-based access controls within WordPress installations, ensuring that only trusted administrators have access to theme customization interfaces. The vulnerability highlights the importance of proper input validation and access control implementation in web applications, aligning with security best practices outlined in OWASP Top Ten and NIST cybersecurity frameworks. Regular security audits of WordPress themes and plugins should be conducted to identify similar authorization weaknesses that could compromise system integrity and user data protection.