{"id":"CVE-2026-118678","aliases":["EUVD-2026-112384","GHSA-4v4v-jr32-r382","GHSA-fvv4-gmv9-xqf5"],"status":"published","title":"n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction","description":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as __proto__ to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.","severity":{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00293,"percentile":0.22197,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-1321"],"published":"2026-10-28T18:59:50Z","modified":"2026-11-02T02:46:04Z","products":[{"vendor":"n8n-io","product":"n8n"}],"references":[{"url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-fvv4-gmv9-xqf5","tags":["vendor-advisory","advisory"]},{"url":"https://www.vulncheck.com/advisories/n8n-before-2.41.4-and-2.42.1-prototype-pollution-dos-via-workflow-history-compaction","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-118678","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-4v4v-jr32-r382"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/118xxx/CVE-2026-118678.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-118678","title":"n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction","description":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as __proto__ to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.","status":"published","published":"2026-10-28T18:59:50.449Z","modified":"2026-10-29T20:54:29.021Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T14:20:03.827373Z"}],"euvd":[{"id":"EUVD-2026-112384","description":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as __proto__ to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.","status":"published","published":"2026-10-28T18:59:50Z","modified":"2026-10-29T20:54:29Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T16:59:14.591479Z"}],"ghsa":[{"id":"GHSA-4v4v-jr32-r382","title":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that...","description":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as __proto__ to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.","status":"published","published":"2026-10-28T21:31:15Z","modified":"2026-10-28T21:31:25Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T15:14:36.959763Z"}],"nvd":[{"id":"CVE-2026-118678","description":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as __proto__ to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.","status":"published","published":"2026-10-28T19:17:33.957Z","modified":"2026-10-29T21:17:16.37Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T14:13:04.6346Z"}],"osv":[{"id":"CVE-2026-118678","title":"n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction","description":"n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as __proto__ to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.","status":"published","published":"2026-10-28T18:59:50.449Z","modified":"2026-11-02T02:46:04.495611524Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T15:44:57.008854Z"}]}}