CVE-2025-2238 in Vikinger Theme
Summary
by MITRE • 04/25/2025
The Vikinger theme for WordPress is vulnerable to privilege in all versions up to, and including, 1.9.30. This is due to insufficient user_meta restrictions in the 'vikinger_user_meta_update_ajax' function. This makes it possible for authenticated attackers, with Subscriber-level access and above, to escalate their privileges to Administrator-level.
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Analysis
by VulDB Data Team • 04/25/2025
The vulnerability identified as CVE-2025-2238 affects the Vikinger theme for WordPress, a popular premium theme used by numerous websites to create engaging social networking experiences. This security flaw represents a critical privilege escalation vulnerability that undermines the core security model of WordPress installations. The vulnerability exists within the theme's implementation of the 'vikinger_user_meta_update_ajax' function, which handles asynchronous updates to user metadata through AJAX requests. Attackers exploiting this vulnerability can manipulate the system's permission model to gain elevated privileges from Subscriber level up to Administrator level, effectively compromising the entire website's security infrastructure. The issue impacts all versions of the theme up to and including version 1.9.30, making it a widespread concern for users who have not updated to newer releases.
The technical root cause of this vulnerability stems from inadequate input validation and insufficient access control mechanisms within the AJAX handler function. Specifically, the 'vikinger_user_meta_update_ajax' function fails to properly verify whether the authenticated user has the necessary permissions to modify user metadata, particularly when dealing with administrative-level attributes. This represents a classic case of insufficient authorization checks, which falls under the CWE-285 category of insufficient authorization. The vulnerability allows authenticated attackers to manipulate the user_meta data structures in ways that should be restricted to administrators only, effectively bypassing WordPress's built-in capability management system. The flaw demonstrates poor security implementation where the system assumes that legitimate users can be trusted to make appropriate changes to other users' metadata without proper validation.
The operational impact of this vulnerability is severe and far-reaching for WordPress site administrators and their users. Once an attacker with Subscriber-level access exploits this vulnerability, they can assume full administrative privileges over the website, gaining access to sensitive data, the ability to modify content, install malicious plugins, change user accounts, and potentially compromise the entire server infrastructure. This privilege escalation allows attackers to perform actions such as modifying user roles, accessing private content, conducting data exfiltration, and establishing persistent backdoors. The vulnerability also poses significant risks to the website's reputation and user trust, as attackers can manipulate the site's content and functionality. The impact extends beyond individual websites to potentially affect entire WordPress ecosystems that rely on the Vikinger theme, particularly when multiple sites share similar vulnerabilities or when attackers use the compromised sites as launch points for further attacks.
Mitigation strategies for CVE-2025-2238 should prioritize immediate action through theme updates to version 1.9.31 or later, which contains the necessary security patches. System administrators should implement comprehensive monitoring of user activities and AJAX requests to detect suspicious patterns that may indicate exploitation attempts. The vulnerability aligns with ATT&CK technique T1078.004 which covers valid accounts and privilege escalation through the use of administrative credentials. Organizations should also consider implementing additional security measures such as role-based access controls, regular security audits, and network segmentation to limit the potential damage from successful exploitation. Security teams should conduct thorough vulnerability assessments to identify any other instances of similar privilege escalation issues within the WordPress ecosystem, particularly focusing on AJAX handlers and user management functions. Regular security training for administrators and developers is crucial to prevent similar issues in future implementations, emphasizing the importance of proper input validation and access control mechanisms in web application development.