CVE-2025-2238: Privilege Escalation Vulnerability in Vikinger WordPress Theme

Overview

CVE-2025-2238 is a critical software vulnerability that resides in the Vikinger theme for WordPress. It poses a substantial security risk to website owners using this theme, as it allows attackers to escalate their privileges from Subscriber-level access to Administrator-level. This potential privilege escalation exposes websites and their data to potential compromise and leakage, causing severe damage to businesses and their reputation.
This vulnerability is significant, considering the popularity of WordPress and the widespread use of the Vikinger theme. The severity of this security flaw underscores the importance of continuous security assessment and prompt patch application to ensure safe and secure operations.

Vulnerability Summary

CVE ID: CVE-2025-2238
Severity: Critical (8.8 CVSS Score)
Attack Vector: Network
Privileges Required: Low (Subscriber-level access)
User Interaction: Required
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Vikinger WordPress Theme | All versions up to and including 1.9.30

How the Exploit Works

The vulnerability lies in the ‘vikinger_user_meta_update_ajax’ function, which lacks sufficient user_meta restrictions. Authenticated attackers with Subscriber-level access or above can exploit this flaw to escalate their privileges to Administrator-level.

Conceptual Example Code

The following is a conceptual HTTP request that an attacker might use to exploit the vulnerability:

POST /wp-admin/admin-ajax.php?action=vikinger_user_meta_update_ajax HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
user_id=1&meta_key=wp_capabilities&meta_value=a%3A1%3A%7Bs%3A13%3A%22administrator%22%3Bs%3A1%3A%221%22%3B%7D

In this example, the `user_id` is set to `1`, which typically refers to the first created user or the administrator. The `meta_key` is `wp_capabilities`, which holds the user role information. The `meta_value` is a URL encoded serialized array that grants administrator privileges.

Mitigation Guidance

Users are urged to apply the vendor-provided patch as soon as possible. Until the patch is applied, users can use a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as a temporary mitigation method. This solution can help detect and block potential exploits targeting this vulnerability. However, this should not be seen as a long-term solution, and applying the security patch should be prioritized.