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Security researchers have revealed two severe, now-patched flaws in the n8n workflow automation platform that could be used to run arbitrary commands on affected hosts. The issues, both rated highly on the CVSS scale, were discovered and reported by Pillar Security.

The problems are tracked as follows:
– CVE-2026-27577 (CVSS 9.4) – an escape from the expression evaluation sandbox that can lead to remote code execution (RCE), and
– CVE-2026-27493 (CVSS 9.5) – unauthenticated expression evaluation exposed through n8n’s Form nodes.

Pillar Security researcher Eilon Cohen explained that CVE-2026-27577 stems from an omission in the AST rewriter inside the expression compiler, which allows certain process calls to pass through without being rewritten. In practice, that flaw gives any authenticated expression the ability to execute commands on the underlying system when used in workflow parameters.

The second issue, CVE-2026-27493, is described by the researcher as a “double-evaluation” problem in the Form nodes. Because n8n’s form endpoints are intentionally public and do not require authentication or an n8n account, this condition can be abused to inject and evaluate expressions from unauthenticated inputs.

In a straightforward exploitation scenario, an attacker can submit a payload into a public “Contact Us” form – for example, in the Name field – to trigger execution of arbitrary shell commands on the server hosting n8n.

n8n’s advisory cautions that an authenticated user who can create or edit workflows could weaponize CVE-2026-27577 by embedding crafted expressions in workflow parameters to cause unintended system command execution on the n8n host. The vendor also notes that combining the public Form node issue (CVE-2026-27493) with an expression sandbox escape like CVE-2026-27577 can escalate into full remote code execution against the host.

The vulnerabilities affect both self-hosted and cloud editions of n8n in these ranges: versions earlier than 1.123.22; versions >= 2.0.0 and = 2.10.0 and < 2.10.1. Fixes are included in n8n releases 2.10.1, 2.9.3, and 1.123.22.

For environments that cannot immediately apply the patch for CVE-2026-27577, n8n recommends restricting who may create or edit workflows to fully trusted administrators and running the application in a locked-down environment with limited OS privileges and network connectivity.

To mitigate CVE-2026-27493 until updates can be applied, the vendor suggests:
– Manually auditing any use of Form nodes to ensure they do not meet the conditions required for exploitation;
– Disabling the Form node by adding n8n-nodes-base.form to the NODES_EXCLUDE environment variable; and
– Disabling the Form Trigger node by adding n8n-nodes-base.formTrigger to NODES_EXCLUDE.

Maintainers warn that these steps are temporary workarounds and do not fully eliminate the risk.

Pillar Security further warned that a successful attacker could retrieve the N8N_ENCRYPTION_KEY environment variable and use it to decrypt all credentials stored in n8n’s database – including AWS credentials, database passwords, OAuth tokens, and other API keys.

In addition to the two defects above, the release candidates 2.10.1, 2.9.3, and 1.123.22 also address two other critical vulnerabilities that could lead to arbitrary code execution when abused by authenticated users who can create or modify workflows:

• CVE-2026-27495 (CVSS 9.4) – a code-injection weakness in the JavaScript Task Runner sandbox that can allow execution outside the sandbox, and
• CVE-2026-27497 (CVSS 9.4) – a flaw in the Merge node when used in SQL query mode that can be used to run arbitrary code and write files on the n8n server.

n8n’s suggested mitigations for these issues are:
– For CVE-2026-27495: run runners in external mode by setting N8N_RUNNERS_MODE=external to reduce the potential impact, and
– For CVE-2026-27497: disable the Merge node by adding n8n-nodes-base.merge to the NODES_EXCLUDE environment variable.

While n8n has not reported any confirmed exploitation of these vulnerabilities in the wild, administrators are strongly encouraged to apply the available patches and follow the recommended hardening steps to protect deployments.