Under the Merge node’s "Combine by SQL" mode in n8n, the insecure AlaSQL sandbox allowed an authenticated user with workflow modification rights to execute arbitrary SQL that read local files or invoked system commands. This flaw is a classic SQL injection that bypasses sandbox restrictions, giving the attacker read and exec capabilities on the host. The effect is remote code execution, enabling full compromise of the n8n instance and potentially the underlying operating system.

The vulnerability applies to all n8n-io installations that run versions older than 2.14.1, 2.13.3, or 1.123.26. Users and administrators of these legacy releases are directly impacted; newer releases are not affected.

With a CVSS base score of 9.4 the flaw is rated critical. No EPSS score is available, and the vulnerability is not listed as a known exploited vulnerability by CISA, but the high severity and requirement for authenticated access suggest that exploitation is plausible in environments with permissive workflow permissions. The most likely attack path is an attacker who gains the right to create or edit workflows, then crafts a malicious Merge node that reads server files or runs commands. Prompt remediation via a patch or temporary restriction of permissions is essential.