CVE-2025-64366: MasterStudy LMS SQL Injection Vulnerability

CVE-2025-64366 Overview

CVE-2025-64366 is a blind SQL injection vulnerability in the Stylemix MasterStudy LMS plugin for WordPress. The flaw affects the masterstudy-lms-learning-management-system plugin in all versions up to and including 3.6.27. It results from improper neutralization of special elements used in SQL commands [CWE-89].

An authenticated attacker with high privileges can inject malicious SQL through vulnerable plugin endpoints. Successful exploitation enables data extraction from the WordPress database and partial impact on database availability. The scope is changed, meaning the affected component can impact resources beyond its security boundary.

Critical Impact
A blind SQL injection in MasterStudy LMS versions through 3.6.27 allows authenticated attackers to extract sensitive data from WordPress databases and degrade service availability.

Affected Products

Stylemix MasterStudy LMS WordPress plugin versions through 3.6.27
WordPress sites running the masterstudy-lms-learning-management-system plugin
Learning management system deployments dependent on the affected plugin

Discovery Timeline

2025-10-31 - CVE-2025-64366 published to the National Vulnerability Database
2026-04-27 - Last updated in NVD database

Technical Details for CVE-2025-64366

Vulnerability Analysis

The vulnerability resides in the MasterStudy LMS plugin's SQL query construction logic. User-supplied input reaches a SQL statement without sufficient sanitization or parameterized binding. The flaw is exploitable over the network and requires high privileges, but no user interaction is needed.

Because the injection is blind, the database does not return query results directly. Attackers infer data through inference techniques such as boolean-based or time-based payloads. This pattern allows enumeration of WordPress tables, including the wp_users table containing password hashes and email addresses.

The Patchstack advisory classifies this as a blind SQL injection affecting all versions up to 3.6.27. The fix is expected in a subsequent plugin release.

Root Cause

The root cause is improper neutralization of special characters in SQL command construction. The plugin concatenates attacker-controlled input into SQL queries instead of using prepared statements with the WordPress $wpdb->prepare() API. This violates secure coding practices defined in [CWE-89].

Attack Vector

An attacker authenticated to WordPress with elevated privileges sends crafted requests to a vulnerable plugin endpoint. The malicious payload contains SQL syntax that alters the underlying query logic. The attacker uses inference techniques to extract data one character or condition at a time.

The vulnerability mechanism is documented in the Patchstack SQL Injection Advisory. No verified public proof-of-concept code is currently available.

Detection Methods for CVE-2025-64366

Indicators of Compromise

HTTP requests to MasterStudy LMS endpoints containing SQL syntax such as UNION, SLEEP(, BENCHMARK(, or encoded SQL operators
Repeated requests from authenticated sessions with response time anomalies suggesting time-based blind injection
Unusual database queries originating from the WordPress PHP process referencing wp_users, wp_usermeta, or LMS-specific tables
WordPress access logs showing privileged account activity from atypical source IP addresses

Detection Strategies

Inspect web server logs for query strings and POST bodies containing SQL keywords directed at /wp-admin/admin-ajax.php or plugin-specific routes
Deploy a Web Application Firewall (WAF) ruleset that flags blind SQL injection signatures including time-delay functions
Enable WordPress database query logging to identify malformed or unexpected SQL statements
Correlate authentication events with subsequent administrative actions to identify compromised privileged accounts

Monitoring Recommendations

Forward WordPress, web server, and database logs to a centralized analytics platform for correlation
Alert on response latency spikes against MasterStudy LMS endpoints that may indicate time-based injection attempts
Track plugin version inventory across WordPress fleets to identify hosts still running versions <= 3.6.27
Monitor outbound traffic from WordPress servers for unexpected data exfiltration patterns

How to Mitigate CVE-2025-64366

Immediate Actions Required

Identify all WordPress installations running the MasterStudy LMS plugin and confirm the installed version
Upgrade the masterstudy-lms-learning-management-system plugin to a release newer than 3.6.27 when available from Stylemix
Review WordPress administrator and instructor accounts for unauthorized access and rotate credentials
Audit recent database activity for signs of exploitation

Patch Information

At time of publication, the Patchstack SQL Injection Advisory confirms the issue affects versions up to and including 3.6.27. Administrators should monitor the Stylemix vendor channel and WordPress plugin repository for a fixed release and apply it immediately.

Workarounds

Restrict access to MasterStudy LMS administrative endpoints using IP allowlists at the web server or WAF
Apply virtual patching rules through a WAF to block SQL injection patterns targeting the affected plugin
Temporarily disable the MasterStudy LMS plugin on internet-facing sites until a patched version is deployed
Enforce least-privilege role assignment to reduce the number of accounts capable of triggering the vulnerable code path

bash

# Example WAF rule (ModSecurity) to block common blind SQLi patterns on plugin endpoints
SecRule REQUEST_URI "@contains masterstudy" \
  "chain,deny,status:403,id:1006401,msg:'Block blind SQLi attempt against MasterStudy LMS'"
  SecRule ARGS "@rx (?i)(sleep\(|benchmark\(|union\s+select|or\s+1=1)" "t:none,t:urlDecodeUni"