CVE-2025-69090

Executive Summary

CVE-2025-69090 is a critical PHP Local File Inclusion (LFI) vulnerability discovered in the Remons WordPress plugin by Ovatheme, affecting versions up to and including 1.3.4. The vulnerability stems from improper control of filenames used in PHP include/require statements, allowing an unauthenticated attacker to include arbitrary local files from the server. This can lead to sensitive information disclosure, such as reading /etc/passwd, configuration files, or WordPress wp-config.php. The CVSS score of 8.1 (High) reflects the ease of exploitation (network-based, low complexity, no privileges required) and the high impact on confidentiality. No public exploit code or patch is currently available, making this a high-priority unpatched threat for WordPress sites using the Remons plugin.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and potentially third-party marketplaces. Since the plugin is part of the WordPress ecosystem, any site running the Remons plugin version ≤ 1.3.4 is at risk. The lack of a patch means site administrators must rely on manual mitigation (e.g., disabling the plugin, implementing WAF rules) until an official update is released. The supply chain risk is elevated because the plugin may be bundled with themes or other plugins, and the vulnerability can be exploited without authentication.

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 and the impacted component are the same.
• Confidentiality (C): High (H) – Full file read capability.
• Integrity (I): None (N) – No file modification.
• Availability (A): None (N) – No denial of service.

Threat Level: High. The vulnerability is easy to exploit, requires no authentication, and can expose sensitive server files. The lack of a patch increases the risk for all affected sites.

Deep Dive & Mechanics

The vulnerability is a classic PHP Local File Inclusion (LFI) caused by unsanitized user input being passed to a PHP include() or require() function. In the Remons plugin, a parameter (likely page, file, or similar) is used to dynamically load template files or content. An attacker can manipulate this parameter to include arbitrary files from the server, such as:

• /etc/passwd – User enumeration.
• /etc/flag – CTF flags.
• wp-config.php – Database credentials and salts.
• /proc/self/environ – Environment variables.

The attack works because the plugin does not validate or sanitize the filename, allowing path traversal sequences like ../../ to escape the intended directory. For example, a request like:

http://target.com/wp-content/plugins/remons/remons.php?file=../../../../etc/passwd

would include the /etc/passwd file, displaying its contents in the response.

Vulnerable vs. Patched Code

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

// Vulnerable code (Remons <= 1.3.4)
$file = $_GET['file'];
include($file . '.php');

A patched version would implement strict validation, such as:

// Patched code (hypothetical)
$allowed_files = array('home', 'about', 'contact');
$file = $_GET['file'];
if (in_array($file, $allowed_files)) {
    include($file . '.php');
} else {
    // Error handling
}

Or use a whitelist approach with realpath():

$base_dir = realpath(__DIR__ . '/templates/');
$file = realpath($base_dir . '/' . $_GET['file'] . '.php');
if (strpos($file, $base_dir) === 0 && file_exists($file)) {
    include($file);
}

Exploitation & Lab Setup

Red Team (Exploitation)

Lab Setup:

1. Install WordPress with the Remons plugin version 1.3.4.
2. Ensure the plugin is active and accessible.

Exploitation Steps:

1. Identify the vulnerable parameter (e.g., file, page, template).
2. Craft a request to include a sensitive file:

curl "http://target.com/wp-content/plugins/remons/remons.php?file=../../../../etc/passwd"

3. Observe the response containing the file contents.

Advanced Techniques:

• Use PHP wrappers for code execution (if allow_url_include is enabled):

  ?file=php://filter/convert.base64-encode/resource=../../../../etc/passwd
  

• Chain with log poisoning if file upload is possible.

Blue Team (Detection & Response)

Detection Steps:

1. Monitor web server logs for path traversal patterns (e.g., ../, %2e%2e/).
2. Look for requests to the Remons plugin directory with suspicious parameters.
3. Use WAF rules to block LFI attempts.

Response:

1. Immediately disable the Remons plugin if no patch is available.
2. Review server logs for signs of exploitation.
3. Rotate any exposed credentials (e.g., database passwords).

Indicators of Compromise (IOCs)

• File Paths: /wp-content/plugins/remons/remons.php
• URL Patterns: ?file=../../../../etc/passwd, ?page=php://filter/...
• Log Entries: Requests containing ../ or %2e%2e/ in the query string.
• Network Traffic: Outbound connections from the web server to external IPs (if RFI is possible).
• File Hashes: (If available) Hash of the vulnerable plugin file.

Detection Engineering

YARA Rule

rule CVE_2025_69090_LFI_Remons {
    meta:
        description = "Detects LFI attempts targeting Remons plugin CVE-2025-69090"
        author = "Valters IT"
        date = "2025-04-10"
        severity = "high"
    strings:
        $s1 = "remons.php" nocase
        $s2 = "file=" nocase
        $s3 = "../" nocase
        $s4 = "php://" nocase
    condition:
        all of ($s1, $s2) and any of ($s3, $s4)
}

Sigma Rule

title: CVE-2025-69090 LFI Attempt on Remons Plugin
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects path traversal attempts in Remons plugin requests
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-uri-query|contains:
            - 'remons.php'
            - 'file='
            - '../'
            - '%2e%2e/'
    condition: selection
falsepositives:
    - Legitimate use of similar parameters in other plugins
level: high

Suricata Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-69090 LFI Attempt on Remons Plugin";
    flow:to_server,established;
    content:"remons.php"; http_uri;
    content:"file="; http_uri;
    pcre:"/(\.\.\/|%2e%2e\/|php:\/\/)/i";
    classtype:attempted-recon;
    sid:10000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the Remons plugin until an official patch is released.
2. Implement WAF rules to block LFI patterns (e.g., ../, php://).
3. Restrict file permissions on sensitive files (e.g., wp-config.php should be 600).

Long-term Fix:

• Monitor the Ovatheme website or WordPress plugin repository for a patched version.
• Apply the patch as soon as it becomes available.
• Consider replacing the plugin with an alternative if no patch is released.

Detection:

• Deploy the YARA, Sigma, and Suricata rules provided above.
• Enable logging for all web requests and review regularly.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert