CVE-2026-56351

Workarounds

If upgrading is not immediately possible, administrators should consider the following temporary mitigations:

• Limit workflow creation and editing permissions to fully trusted users only.
• Disable the MySQL, PostgreSQL, and Microsoft SQL nodes by adding n8n-nodes-base.mySql, n8n-nodes-base.postgres, and n8n-nodes-base.microsoftSql to the NODES_EXCLUDE environment variable.

These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

Credit

Reporter: Pawel Bednarz from the NATO Cyber Security Centre (NCSC)

An authenticated user with permission to create or modify workflows and access to a database credential could unknowingly create a workflow that was vulnerable to SQL injection, even while expecting inputs to be handled safely through escaped parameters. By supplying specially crafted table or column names, an attacker could inject arbitrary SQL because the MySQL, PostgreSQL, and Microsoft SQL nodes did not escape identifier values when constructing queries, enabling injection through node configuration parameters.

Untrusted input alters a database query, allowing the attacker to read or modify data the query was not intended to access. Typical impact: data disclosure or modification.

CVE-2026-56351 has a CVSS score of 8.2 (Medium). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.4.0); upgrading removes the vulnerable code path.

Kodem intelligence

The issue has been fixed in n8n version 2.4.0. Users should upgrade to this version or later to remediate the vulnerability.

1. What is CVE-2026-56351? CVE-2026-56351 is a medium-severity SQL injection vulnerability in n8n (npm), affecting versions < 2.4.0. It is fixed in 2.4.0. Untrusted input alters a database query, allowing the attacker to read or modify data the query was not intended to access.
2. How severe is CVE-2026-56351? CVE-2026-56351 has a CVSS score of 8.2 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of n8n are affected by CVE-2026-56351? n8n (npm) versions < 2.4.0 is affected.
4. Is there a fix for CVE-2026-56351? Yes. CVE-2026-56351 is fixed in 2.4.0. Upgrade to this version or later.
5. Is CVE-2026-56351 exploitable, and should I be worried? Whether CVE-2026-56351 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-56351 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-56351? Upgrade n8n to 2.4.0 or later.