{"id":"CVE-2026-110842","title":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability in the MCP workflow-validation tool, whose interpreter evaluates caller-supplied code in the main process, reads inherited properties, and permits as…","summary":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability in the MCP workflow-validation tool, whose interpreter evaluates caller-supplied code in the main process, reads inherited properties, and permits as…","severity":"high","cvss":7.7,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","cwe":["CWE-1321"],"vendor":"n8n-io","product":"n8n","affected":["n8n < 2.41.4","n8n >= 2.42.0 < 2.42.1"],"published":"2026-10-14","updated":"2026-10-15","sourceUpdated":"2026-10-15T14:17:20.867","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-110842","references":[{"url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-5jr4-xmvf-frmj","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/n8n-before-2.41.4-and-2.42.1-prototype-pollution-via-mcp-workflow-validation-interpreter","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T13:44:32.171824Z"},"cvssSource":"cna","ingestedAt":"2026-10-15T00:02:07.175Z","epss":0.00312,"epssPercentile":0.23974,"slug":"CVE-2026-110842","body":"## Overview\n\nn8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability in the MCP workflow-validation tool, whose interpreter evaluates caller-supplied code in the main process, reads inherited properties, and permits assignment onto shared prototypes. An authenticated member holding only a workflow:read grant can replace a built-in method with one returning a truthy value so server-side permission checks accept unheld scopes, enabling takeover of owner accounts not protected by MFA.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":42,"depthScoreParts":{"impact":42.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":221973,"id":"CVE-2026-110842","ts":1792039696965,"field":"cvss","old":null,"new":"7.7"},{"seq":221972,"id":"CVE-2026-110842","ts":1792039696965,"field":"severity","old":"none","new":"high"}]}