Critical n8n Expression Sandbox Escape Leading to Authenticated RCE (CVE-2026-25049)

A critical remote code execution issue in the n8n open-source workflow automation platform, tracked as CVE-2026-25049 (also published as GHSA-6cqr-8cfr-67f8), allows an authenticated user with permission to create or modify workflows to escape n8n’s expression sandbox and execute arbitrary system commands on the underlying host. The flaw stems from insufficient input sanitization/weak sandboxing in n8n’s expression evaluation (server-side JavaScript) and was identified during follow-up analysis after an earlier critical n8n vulnerability (CVE-2025-68613) was patched; researchers report the new issue effectively bypasses prior mitigations.

Reporting indicates exploitation can lead to full compromise of the n8n instance, including access to the filesystem and the ability to steal stored credentials and secrets (e.g., API keys, OAuth tokens) and sensitive configuration, with potential for pivoting into connected internal services and cloud accounts in multi-tenant deployments. Public reporting also notes public exploits are available. n8n maintainers state the issue is patched, and affected organizations should upgrade to fixed releases (1.123.17 and 2.5.2), as versions prior to 1.123.17 and 2.5.2 are impacted.