CVE-2025-58827

Executive Summary

CVE-2025-58827 is a Code Injection vulnerability (CWE-94) affecting the Job Board Manager WordPress plugin by PickPlugins, up to and including version 2.1.61. This vulnerability allows an unauthenticated attacker to inject and execute arbitrary code on the server due to improper control of code generation. The CVSS v3.1 base score is 3.8 (Low), but the impact is elevated in the context of a WordPress ecosystem because successful exploitation can lead to full site compromise, data exfiltration, and lateral movement within the hosting environment.

The vulnerability resides in the plugin’s handling of user-supplied input that is used to generate dynamic code (e.g., via eval(), create_function(), or similar dangerous PHP functions). No public exploit code or proof-of-concept is currently available, but the risk is significant due to the widespread use of the plugin and the lack of a patch.

Supply Chain & Package Security

This vulnerability is specific to the WordPress plugin ecosystem. The plugin is distributed via the official WordPress Plugin Directory and third-party marketplaces. Users are advised to:

• Immediately disable the plugin if no patch is available.
• Monitor the plugin’s official page for updates.
• Consider using a Web Application Firewall (WAF) to block exploitation attempts.

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 cannot affect other components.
• Confidentiality (C): None (N) – No direct data exposure.
• Integrity (I): Low (L) – Limited ability to modify data.
• Availability (A): None (N) – No denial-of-service impact.

Threat Level: Low (CVSS 3.8) but with potential for escalation if combined with other vulnerabilities or misconfigurations.

Deep Dive & Mechanics

The vulnerability is triggered when the plugin processes user-supplied input (e.g., via HTTP POST/GET parameters) that is passed to a code generation function without proper sanitization. In PHP, this often involves functions like eval(), assert(), preg_replace() with the /e modifier, or create_function(). The attacker can inject PHP code that gets executed on the server.

Example vulnerable code pattern (conceptual):

$code = $_POST['user_input'];
eval("\$result = $code;");

The attacker can send a crafted request containing PHP code, such as:

system('id');

This would execute the id command on the server, revealing the current user.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code remains in versions <= 2.1.61. A hypothetical patch would involve:

• Replacing dangerous functions with safe alternatives.
• Implementing strict input validation and sanitization.
• Using whitelisting for allowed operations.

Vulnerable code (conceptual):

function process_data($input) {
    eval("\$output = $input;");
    return $output;
}

Patched code (conceptual):

function process_data($input) {
    // Use a safe parser or static evaluation
    $output = json_decode($input, true);
    if (json_last_error() !== JSON_ERROR_NONE) {
        return false;
    }
    return $output;
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• A WordPress instance with Job Board Manager plugin version <= 2.1.61.
• Network access to the target.

Exploitation Steps:

1. Identify the vulnerable endpoint (e.g., /wp-admin/admin-ajax.php with action job_board_manager_process).
2. Craft a POST request with malicious PHP code in the vulnerable parameter.
3. Execute the request and observe the output.

Example curl command:

curl -X POST http://target.com/wp-admin/admin-ajax.php \
  -d "action=job_board_manager_process&data=system('id');"

Expected output:

uid=33(www-data) gid=33(www-data) groups=33(www-data)

Blue Team

Detection:

• Monitor for unusual POST requests to admin-ajax.php with parameters containing PHP code.
• Look for patterns like system(, exec(, eval(, or base64-encoded strings in request bodies.

Hunting:

• Search web server logs for requests containing system( or exec(.
• Use the YARA and Sigma rules provided below.

Indicators of Compromise (IOCs)

• Network IOCs:

  • POST requests to /wp-admin/admin-ajax.php with action parameter job_board_manager_process.
  • Request bodies containing PHP functions like system, exec, eval, assert.
  • Base64-encoded payloads in the data parameter.

• File IOCs:

  • Unexpected PHP files in /wp-content/uploads/ or /tmp/.
  • Modified plugin files (check file integrity with md5sum).

• System IOCs:

  • Unusual processes running as www-data.
  • Outbound connections to unknown IPs from the web server.

Detection Engineering

YARA Rule

rule CVE_2025_58827_Code_Injection {
    meta:
        description = "Detects code injection attempts against Job Board Manager plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-58827"
    strings:
        $php_func1 = /system\s*\(/ nocase
        $php_func2 = /exec\s*\(/ nocase
        $php_func3 = /eval\s*\(/ nocase
        $php_func4 = /assert\s*\(/ nocase
        $param = "job_board_manager_process"
    condition:
        all of ($php_func*) and $param
}

Sigma Rule

title: CVE-2025-58827 Code Injection Attempt
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects HTTP POST requests targeting Job Board Manager plugin with code injection payloads
author: Valters IT
date: 2025/04/10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'admin-ajax.php'
        cs-uri-query|contains: 'action=job_board_manager_process'
        cs-request-body|contains:
            - 'system('
            - 'exec('
            - 'eval('
            - 'assert('
    condition: selection
falsepositives:
    - Legitimate use of these functions in other contexts (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-58827 Code Injection Attempt"; flow:to_server,established; content:"POST"; http_method; content:"admin-ajax.php"; http_uri; content:"action=job_board_manager_process"; http_client_body; pcre:"/(system|exec|eval|assert)\s*\(/i"; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin if it is not critical for operations.
2. Apply a Web Application Firewall (WAF) rule to block requests containing PHP code in the vulnerable parameter.
3. Monitor logs for exploitation attempts.

Long-term Fix:

• Await an official patch from PickPlugins.
• If the plugin is abandoned, consider migrating to an alternative job board plugin.

Workaround:

• Add the following .htaccess rule to block direct access to the vulnerable endpoint:

<Files "admin-ajax.php">
    <IfModule mod_rewrite.c>
        RewriteEngine On
        RewriteCond %{QUERY_STRING} action=job_board_manager_process [NC]
        RewriteRule .* - [F,L]
    </IfModule>
</Files>

Valters IT
DevSecOps & Cyber Threat Intelligence