CVE-2026-5207: LifterLMS WordPress Plugin SQLi Vulnerability

CVE-2026-5207 Overview

The LifterLMS plugin for WordPress contains a SQL Injection vulnerability in the 'order' parameter affecting all versions up to and including 9.2.1. This vulnerability stems from insufficient escaping of user-supplied input and inadequate preparation of SQL queries within the plugin's reporting functionality. Authenticated attackers with Instructor-level access or higher who possess the edit_post capability on quizzes can exploit this flaw to append malicious SQL queries to existing database queries, potentially extracting sensitive information from the WordPress database.

Critical Impact

Authenticated attackers with Instructor privileges can extract sensitive database information including user credentials, personal data, and site configuration through SQL injection attacks targeting the quiz reporting functionality.

Affected Products

• LifterLMS WordPress Plugin versions up to and including 9.2.1
• WordPress sites utilizing LifterLMS for learning management
• Quiz reporting functionality within LifterLMS admin interface

Discovery Timeline

• 2026-04-11 - CVE CVE-2026-5207 published to NVD
• 2026-04-13 - Last updated in NVD database

Technical Details for CVE-2026-5207

Vulnerability Analysis

This SQL Injection vulnerability (CWE-89) exists within the LifterLMS plugin's quiz reporting tables functionality. The vulnerable code resides in llms.table.quiz.non.attempts.php and the llms.ajax.handler.php files, where user-controlled input from the 'order' parameter is incorporated into SQL queries without proper sanitization or parameterized query preparation.

The attack requires authentication with at least Instructor-level privileges and the edit_post capability on quiz content. While this limits the attack surface compared to unauthenticated vulnerabilities, the potential for data exfiltration remains significant in multi-instructor environments or compromised instructor accounts.

Root Cause

The root cause is insufficient input validation and improper SQL query construction. The 'order' parameter, which controls the sorting order of quiz attempt data in administrative reporting tables, is not properly escaped before being concatenated into SQL queries. WordPress provides the $wpdb->prepare() method specifically to prevent SQL injection, but this protection was not adequately implemented for the affected parameter.

Attack Vector

The vulnerability is exploitable over the network by authenticated users. An attacker with valid Instructor credentials can manipulate the 'order' parameter in requests to the quiz reporting tables endpoint. By injecting SQL syntax into this parameter, the attacker can modify the query logic to extract data from arbitrary database tables, including the wp_users table containing password hashes and email addresses, or custom tables containing student information.

The attack flow involves:

1. Authenticating to WordPress with Instructor-level access
2. Navigating to quiz reporting functionality
3. Intercepting and modifying the 'order' parameter in AJAX requests
4. Injecting SQL payloads to extract database contents through error-based or blind SQL injection techniques

For detailed technical analysis, refer to the WordPress Plugin Code View and the Wordfence Vulnerability Report.

Detection Methods for CVE-2026-5207

Indicators of Compromise

• Unusual database queries containing SQL injection patterns in web server logs
• Unexpected AJAX requests to LifterLMS reporting endpoints with malformed 'order' parameters
• Database access patterns indicating bulk data extraction from sensitive tables
• Instructor accounts exhibiting unusual activity patterns or accessing reports outside normal hours

Detection Strategies

• Monitor web application logs for requests containing SQL injection signatures such as UNION SELECT, ' OR '1'='1, or encoded equivalents targeting LifterLMS endpoints
• Implement Web Application Firewall (WAF) rules to detect SQL injection attempts in POST/GET parameters
• Enable WordPress database query logging to identify anomalous query patterns from the LifterLMS plugin
• Review authentication logs for Instructor-level account access from unusual IP addresses or geographic locations

Monitoring Recommendations

• Configure SIEM alerts for SQL injection patterns in requests to /wp-admin/admin-ajax.php with LifterLMS actions
• Monitor database performance metrics for unexpected query execution times indicating injection attempts
• Audit Instructor-level user accounts and their associated capabilities regularly
• Implement rate limiting on administrative AJAX endpoints to slow potential automated exploitation

How to Mitigate CVE-2026-5207

Immediate Actions Required

• Update LifterLMS plugin to the latest patched version immediately
• Review Instructor-level user accounts and remove unnecessary privileges
• Audit database access logs for potential exploitation attempts prior to patching
• Consider temporarily restricting Instructor access to quiz reporting if immediate patching is not possible

Patch Information

The vulnerability has been addressed in versions following 9.2.1. The patch implements proper SQL query preparation using WordPress's $wpdb->prepare() method to sanitize the 'order' parameter before inclusion in database queries. Review the WordPress Code Changeset for technical details on the implemented fix.

Workarounds

• Restrict Instructor-level account creation to trusted users only until patching is complete
• Implement a Web Application Firewall with SQL injection detection rules to filter malicious requests
• Disable quiz reporting functionality temporarily by removing Instructor capabilities if patching cannot be performed immediately
• Monitor database queries using a security plugin capable of detecting SQL injection patterns

# Verify LifterLMS version and update via WP-CLI
wp plugin list --name=lifterlms --fields=name,version,update_version

# Update LifterLMS to the latest version
wp plugin update lifterlms

# Verify the update was successful
wp plugin list --name=lifterlms --fields=name,version