Overview
The CVE-2025-3520 vulnerability is a significant cybersecurity concern for WordPress websites using the Avatar plugin. This vulnerability has to do with an arbitrary file deletion flaw found in all versions of the plugin up to 0.1.4. If exploited, the vulnerability can lead to remote code execution, making it possible for attackers to gain complete control over the compromised server. It is highly relevant to all WordPress administrators, particularly those who use the Avatar plugin, and the wider web development community due to its potential for system compromise or data leakage.
Vulnerability Summary
CVE ID: CVE-2025-3520
Severity: High (8.1 CVSS score)
Attack Vector: Network
Privileges Required: Low (Subscriber-level access)
User Interaction: Required
Impact: System compromise or data leakage
Affected Products
No phone number, email, or personal info required.
Product | Affected Versions
WordPress Avatar Plugin | 0.1.4 and below
How the Exploit Works
The CVE-2025-3520 vulnerability arises due to insufficient file path validation in a function within the Avatar plugin. An attacker, with just subscriber-level access, can exploit this flaw to delete arbitrary files on the server. The deletion of certain files, such as wp-config.php, could lead to remote code execution.
Remote code execution means that an attacker can run arbitrary commands on the server, thereby gaining complete control over it. This could lead to system compromise, data leakage, or a complete shutdown, depending on the attacker’s intentions.
Conceptual Example Code
Here’s a conceptual example of how the vulnerability might be exploited. In this case, the attacker sends an HTTP POST request to the server with a malicious payload targeting a sensitive file for deletion:
POST /wp-admin/admin-ajax.php?action=avatar_delete&file=../../wp-config.php HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
Cookie: wordpress_logged_in_[hash]=[username|timestamp|hash]In this request, `avatar_delete` is the action parameter taken from the Avatar plugin, and `file` is the parameter used by the plugin to specify the file to delete. The attacker uses directory traversal (`../../`) to move up in the directory structure and target the `wp-config.php` file.
Please note that this is a conceptual example meant to illustrate how an attack might occur. Actual attacks may vary based on the attacker’s tactics and the specific configuration of the target server.
Mitigation Guidance
To mitigate this vulnerability, WordPress administrators using the Avatar plugin should apply the vendor patch as soon as it is available. In the meantime, or if a patch is not available, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can provide temporary mitigation by blocking or alerting on malicious traffic patterns. Administrators should also consider limiting the permissions of subscriber-level users wherever possible to reduce the risk of exploitation. Regularly updating all WordPress plugins and core files can help prevent future vulnerabilities.