CVE-2025-53204: Eventlist PHP File Inclusion Vulnerability

CVE-2025-53204 Overview

CVE-2025-53204 is a PHP Local File Inclusion (LFI) vulnerability in the ovatheme eventlist WordPress plugin. The flaw stems from improper control of filename arguments used in PHP include or require statements [CWE-98]. Attackers can exploit this issue over the network without authentication or user interaction, although the attack complexity is rated high. Successful exploitation can lead to disclosure of sensitive server-side files, execution of attacker-controlled PHP code already present on the host, and full compromise of the affected WordPress site. The vulnerability affects all versions of the eventlist plugin up to and including 1.9.2.

Critical Impact

Unauthenticated attackers can include arbitrary local PHP files, leading to confidentiality, integrity, and availability impact on the WordPress host.

Affected Products

• ovatheme eventlist WordPress plugin versions through 1.9.2
• WordPress sites running the plugin with default configurations
• Hosting environments where local files are reachable by the web server user

Discovery Timeline

• 2025-08-20 - CVE-2025-53204 published to the National Vulnerability Database (NVD)
• 2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-53204

Vulnerability Analysis

The eventlist plugin passes user-supplied input into a PHP include or require statement without sufficient sanitization or allow-listing. This pattern enables Local File Inclusion, where an attacker controls part of the filename string that PHP loads and executes. Because PHP treats included files as code, any included .php file runs in the context of the web server.

The issue is classified under [CWE-98] (Improper Control of Filename for Include/Require Statement in PHP Program). The CVSS vector indicates a network-based, unauthenticated attack with high impact across confidentiality, integrity, and availability. The high attack complexity reflects conditions such as required knowledge of file paths or environment specifics.

Root Cause

The root cause is the use of untrusted input as a path argument to a PHP file inclusion function. The plugin does not constrain the input to a fixed allow-list of template files, does not strip directory traversal sequences, and does not validate that the resolved path stays within an expected directory. As a result, traversal sequences and absolute paths can redirect inclusion to attacker-chosen files on the local filesystem.

Attack Vector

An unauthenticated remote attacker sends a crafted HTTP request to a vulnerable plugin endpoint, supplying a manipulated parameter that the plugin passes to include or require. The attacker can target local PHP files placed through other channels, such as uploaded media, log files containing injected PHP, or session files. Successful inclusion runs the targeted file as PHP code under the web server user, enabling site takeover, credential theft from wp-config.php, or pivoting into the underlying host.

No verified public proof-of-concept code is available at this time. See the Patchstack advisory for additional technical context.

Detection Methods for CVE-2025-53204

Indicators of Compromise

• HTTP requests to eventlist plugin endpoints containing directory traversal sequences such as ../ or URL-encoded variants like %2e%2e%2f
• Requests referencing sensitive local paths, for example wp-config.php, /etc/passwd, or PHP session files under /tmp or /var/lib/php/sessions
• Unexpected PHP processes or outbound connections originating from the web server immediately after plugin requests
• New or modified PHP files in wp-content/uploads/ indicating staged inclusion payloads

Detection Strategies

• Inspect web server access logs for parameter values containing path characters passed to eventlist plugin URLs
• Deploy Web Application Firewall (WAF) rules that flag LFI patterns targeting WordPress plugin paths
• Correlate plugin requests with subsequent file modifications, new admin user creation, or scheduled task changes
• Hunt for inclusion of uploaded files by matching upload events to later HTTP requests referencing the same filenames

Monitoring Recommendations

• Enable PHP error_log capture for include/require failures and review repeated failed inclusions from the same client
• Monitor file integrity for wp-content/plugins/eventlist/ and core WordPress files to detect tampering
• Alert on anonymous access patterns that produce HTTP 200 responses from plugin endpoints not normally hit by unauthenticated users

How to Mitigate CVE-2025-53204

Immediate Actions Required

• Identify all WordPress installations running the ovatheme eventlist plugin and confirm installed versions
• Disable or remove the eventlist plugin on sites that cannot immediately apply a vendor fix
• Rotate WordPress administrator credentials and any secrets stored in wp-config.php if exploitation is suspected
• Review web server logs from before the patch date for inclusion attempts and signs of compromise

Patch Information

The vulnerability affects eventlist versions through 1.9.2. Refer to the Patchstack advisory for the latest fixed version information from the vendor and apply the patched release as soon as it is available.

Workarounds

• Restrict access to the plugin's vulnerable endpoints using WAF rules or web server access controls until a patch is applied
• Set PHP open_basedir to limit file inclusion scope to the WordPress document root and required directories
• Disable PHP execution in wp-content/uploads/ via web server configuration to reduce the impact of staged LFI payloads
• Apply least privilege to the web server user so accessible local files do not include sensitive system paths

# Example: disable PHP execution in WordPress uploads directory (Apache)
<Directory "/var/www/html/wp-content/uploads">
    <FilesMatch "\.php$">
        Require all denied
    </FilesMatch>
</Directory>

# Example: restrict PHP file access scope (php.ini)
open_basedir = "/var/www/html:/tmp"