CVE-2026-54311

Name of the Vulnerable Software and Affected Versions n8n versions prior to 2.25.7 n8n versions prior to 2.26.2

Description An authenticated user with permissions to create or modify workflows can pollute the sandbox used by the Merge node's SQL Query mode. Since the sandbox context is cached and reused across all workflow executions on an instance, prototype mutations introduced by one user persist in subsequent Merge SQL executions for other users or projects. This allows a low-privileged attacker to intercept workflow data processed by other users on the same instance. This issue specifically affects multi-user instances where multiple users have permission to create and execute workflows using the Merge node in SQL Query mode.

Recommendations Update to version 2.25.7. Update to version 2.26.2. Limit workflow creation and editing permissions to fully trusted users only. Disable the Merge node by adding n8n-nodes-base.merge to the NODES EXCLUDE environment variable.