CVE-2026-56351: n8n SQL Injection in Database Nodes – Patch Guidance & Detection

Technical summary

CVE-2026-56351 is a SQL injection vulnerability in n8n versions prior to 2.4.0 stemming from insufficient input validation on identifier parameters in MySQL, PostgreSQL, and Microsoft SQL Server database nodes. The vulnerability exists in node configuration parameters where table and column names are processed without proper escaping or parameterization. An authenticated attacker with workflow creation privileges can inject arbitrary SQL through these unescaped identifier values, leading to unauthorized command execution against backend databases. The CVSS v3.1 score of 8.2 (HIGH) reflects the high impact on confidentiality and integrity, moderated by the requirement for local authentication and higher attack complexity.

Business impact

Successful exploitation could result in unauthorized access to sensitive data stored in databases connected through n8n workflows, modification or deletion of critical records, and potential compliance violations depending on the nature of affected data. Organizations using n8n to orchestrate processes involving customer data, financial records, or intellectual property face elevated risk. Automated workflows may be compromised to exfiltrate or corrupt data without direct user visibility. Recovery efforts could be extensive if malicious modifications propagate through dependent systems.

Affected systems

n8n versions before 2.4.0 are vulnerable. All deployments running earlier versions that leverage MySQL, PostgreSQL, or Microsoft SQL Server nodes in any workflow are in scope. The vulnerability is not limited to specific deployment types (cloud, self-hosted, containerized) but rather to the core database node functionality. Organizations should inventory all n8n instances and their associated workflow configurations to identify exposure.

Exploitability

Exploitation requires an authenticated n8n account with workflow creation permissions. An attacker cannot exploit this vulnerability unauthenticated or without workflow design access. However, this is a realistic threat model for insider threats, compromised user credentials, or intentional misuse by a trusted analyst. The attack requires no user interaction and no out-of-band actions—injection occurs through standard workflow configuration interfaces. The vulnerability is not currently listed on CISA's Known Exploited Vulnerabilities catalog, though this does not diminish the inherent risk if an attacker with access exists.

Remediation

Upgrade n8n to version 2.4.0 or later, which remediates the SQL injection vulnerability through proper input validation and parameterized query construction in database nodes. Organizations unable to upgrade immediately should restrict workflow creation and editing permissions to trusted users only, audit existing workflows for suspicious table or column name patterns, and implement database-level access controls to limit the blast radius of any potential injection. Consider deploying network segmentation to isolate n8n instances from production databases where feasible.

Patch guidance

Apply the upgrade to n8n 2.4.0 or later as soon as possible. Verify with your n8n deployment documentation for upgrade procedures specific to your environment (cloud-hosted, self-managed, Docker, Kubernetes, etc.). Test the upgrade in a non-production environment first to confirm compatibility with existing workflows. Review release notes for any breaking changes or required configuration adjustments. If running n8n via container orchestration, update image tags and redeploy. For organizations on extended maintenance or older versions, contact n8n support for backport availability or extended support timelines.

Detection guidance

Monitor n8n workflow audit logs for unusual database node configurations, particularly those with special characters or SQL syntax in table or column name fields. Review workflow creation and modification events for users who do not typically create workflows or whose actions deviate from normal patterns. Examine database query logs for unexpected or malformed SQL statements originating from n8n connection strings. Implement intrusion detection rules targeting SQL injection patterns in database traffic from n8n instances. Capture and analyze workflow definitions for suspicious naming patterns or encoded payloads in node parameters.

Why prioritize this

This vulnerability rates HIGH priority due to the combination of high confidentiality and integrity impact, broad applicability across database platforms, and the realistic insider-threat attack vector. While authentication is required, many organizations grant workflow creation rights to multiple users. The ability to compromise data integrity without detection until after the fact makes this a business-critical threat. Immediate patching is recommended for all affected instances, particularly those connected to production or sensitive databases.

Risk score, explained

The CVSS v3.1 score of 8.2 reflects: (1) Network-accessible attack surface; (2) High attack complexity due to authentication and configuration requirements; (3) Low privileges required (authenticated user role); (4) High confidentiality impact (SQL injection enables data exfiltration); (5) High integrity impact (unauthorized modification or deletion); (6) No availability impact (DoS not inherent to vulnerability); (7) Scope change (workflow compromise can affect downstream systems). The score is elevated by the breadth of supported databases and the lack of inherent constraints on query complexity, balanced by the prerequisite authentication and the need for workflow design access.

Frequently asked questions