CVE-2026-33058: Kanboard SQL Injection Vulnerability

CVE-2026-33058 Overview

CVE-2026-33058 is an authenticated SQL Injection vulnerability affecting Kanboard, an open-source project management software focused on Kanban methodology. This vulnerability allows authenticated attackers with permission to add users to a project to inject malicious SQL queries, potentially dumping the entirety of the Kanboard database and compromising sensitive project management data.

Critical Impact
Authenticated users with project user management permissions can exploit this SQL injection flaw to extract complete database contents, including user credentials, project data, and sensitive business information.

Affected Products

Kanboard versions prior to 1.2.51

Discovery Timeline

2026-03-18 - CVE-2026-33058 published to NVD
2026-03-18 - Last updated in NVD database

Technical Details for CVE-2026-33058

Vulnerability Analysis

This SQL Injection vulnerability (CWE-89) exists in Kanboard's user management functionality. The flaw is triggered when authenticated users exercise their permission to add users to a project. The application fails to properly sanitize or parameterize user-supplied input before incorporating it into SQL queries, allowing attackers to manipulate query logic and extract unauthorized data from the database.

The vulnerability requires network access and low-privilege authentication (project management permissions), but once these prerequisites are met, exploitation is straightforward with no user interaction required. The impact extends beyond the immediate application context, potentially affecting the confidentiality and integrity of the entire database system.

Root Cause

The root cause of CVE-2026-33058 is improper input validation and lack of parameterized queries in the code path responsible for adding users to projects. User-controlled input is concatenated directly into SQL statements without proper sanitization, escaping, or the use of prepared statements. This classic SQL Injection pattern allows attackers to break out of the intended query structure and execute arbitrary SQL commands.

Attack Vector

The attack vector is network-based, requiring an authenticated attacker with permission to add users to a Kanboard project. The attacker crafts malicious input containing SQL syntax when performing user addition operations. Due to the lack of input sanitization, this input is directly incorporated into database queries, allowing the attacker to:

Extract sensitive data from any table in the database
Enumerate database structure and schema information
Potentially modify or delete data depending on database permissions
Access user credentials, session tokens, and other authentication material

The vulnerability allows complete database extraction, making it particularly dangerous for organizations storing sensitive project data, client information, or proprietary business processes within Kanboard.

Detection Methods for CVE-2026-33058

Indicators of Compromise

Unusual database query patterns in application logs, particularly involving UNION SELECT statements or error-based injection techniques
Unexpected data access patterns or large data exports from the Kanboard database
Anomalous user addition requests containing special SQL characters such as single quotes, semicolons, or SQL keywords
Database error messages appearing in application responses or logs indicating SQL syntax errors

Detection Strategies

Implement Web Application Firewall (WAF) rules to detect SQL injection patterns in HTTP requests targeting Kanboard user management endpoints
Monitor database query logs for suspicious patterns including UNION-based injection, time-based blind injection, or error-based extraction techniques
Deploy application-layer intrusion detection to identify malformed requests to project user management functions
Configure alerts for database activities involving bulk data extraction or unusual schema queries

Monitoring Recommendations

Enable detailed logging for all database queries executed by the Kanboard application
Monitor authentication logs for accounts with project management permissions exhibiting unusual activity patterns
Set up alerts for database connection anomalies or unexpected query volumes
Review access logs for the project user management functionality for suspicious request patterns

How to Mitigate CVE-2026-33058

Immediate Actions Required

Upgrade Kanboard to version 1.2.51 or later immediately
Review database access logs for any evidence of exploitation attempts
Audit user accounts with project management permissions and verify their legitimacy
Consider rotating database credentials and session tokens as a precautionary measure
Implement network segmentation to limit database access from the application layer

Patch Information

Kanboard version 1.2.51 addresses this SQL injection vulnerability by implementing proper input sanitization and parameterized queries in the affected code path. Organizations should upgrade to this version or later as soon as possible. For detailed information about the fix, refer to the GitHub Security Advisory.

Workarounds

Restrict project user management permissions to only essential, trusted administrators until patching is complete
Implement a Web Application Firewall (WAF) with SQL injection detection rules in front of the Kanboard application
Enable database query auditing and configure alerts for suspicious SQL patterns
Consider temporarily disabling the affected user management functionality if operationally feasible
Apply network-level access controls to limit who can reach the Kanboard application

bash

# Example WAF rule pattern to help detect SQL injection attempts
# Note: This is a defense-in-depth measure and does not replace patching
# ModSecurity rule example:
SecRule ARGS "@detectSQLi" "id:1001,phase:2,deny,status:403,msg:'SQL Injection Attempt Detected'"