{"id":"CVE-2026-56356","aliases":["EUVD-2026-40444","GHSA-3c7f-5hgj-h279","GHSA-99wx-hwrx-8g4w"],"status":"published","title":"n8n - Stored Cross-Site Scripting in Chat Trigger Node Custom CSS Field","description":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page.","severity":{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.0025,"percentile":0.1653,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-79"],"published":"2026-03-27T18:06:49Z","modified":"2026-10-31T02:30:37Z","fixes":[{"ecosystem":"npm","package":"n8n","fixed_in":["1.123.27","2.14.1","2.13.3"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"n8n","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.123.27"}]}]},{"source":"ghsa","ecosystem":"npm","package":"n8n","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.14.0"},{"last_affected":"2.14.0"},{"fixed":"2.14.1"}]}],"versions":["2.14.0"]},{"source":"ghsa","ecosystem":"npm","package":"n8n","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.0.0-rc.0"},{"fixed":"2.13.3"}]}]},{"source":"osv","ecosystem":"npm","package":"n8n","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.123.27"}]}]},{"source":"osv","ecosystem":"npm","package":"n8n","ranges":[{"type":"SEMVER","events":[{"introduced":"2.14.0"},{"fixed":"2.14.1"}]}],"versions":["2.14.0"]},{"source":"osv","ecosystem":"npm","package":"n8n","ranges":[{"type":"SEMVER","events":[{"introduced":"2.0.0-rc.0"},{"fixed":"2.13.3"}]}]}],"products":[{"vendor":"n8n","product":"n8n"},{"vendor":"n8n-io","product":"n8n"}],"references":[{"url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-3c7f-5hgj-h279","tags":["vendor-advisory","Mitigation","Vendor Advisory","advisory","web"]},{"url":"https://www.vulncheck.com/advisories/n8n-stored-cross-site-scripting-in-chat-trigger-node-custom-css-field","tags":["third-party-advisory","Third Party Advisory","advisory"]},{"url":"https://github.com/advisories/GHSA-3c7f-5hgj-h279"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56356","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-99wx-hwrx-8g4w"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56356.json","tags":["advisory"]},{"url":"https://github.com/n8n-io/n8n","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-56356","title":"n8n - Stored Cross-Site Scripting in Chat Trigger Node Custom CSS Field","description":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page.","status":"published","published":"2026-06-30T22:08:35.484Z","modified":"2026-10-29T21:15:46.988Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T13:36:51.6229Z"}],"euvd":[{"id":"EUVD-2026-40444","description":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page.","status":"published","published":"2026-06-30T22:08:35Z","modified":"2026-10-29T21:15:46Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-02T16:59:14.250155Z"}],"ghsa":[{"id":"GHSA-3c7f-5hgj-h279","title":"n8n has XSS in Chat Trigger Node through Custom CSS","description":"## Impact\nAn authenticated user with permission to create or modify workflows could inject malicious JavaScript into the Custom CSS field of the Chat Trigger node. Due to a misconfiguration in the `sanitize-html` library, the sanitization could be bypassed, resulting in stored XSS on the public chat page. Any user visiting the chat URL would be affected.\n\n## Patches\nThe issue has been fixed in n8n versions 1.123.27, 2.13.3, and 2.14.1. Users should upgrade to one of these versions or later to remediate the vulnerability.\n\n## Workarounds\nIf upgrading is not immediately possible, administrators should consider the following temporary mitigations:\n- Limit workflow creation and editing permissions to fully trusted users only.\n- Disable the Chat Trigger node by adding `@n8n/n8n-nodes-langchain.chatTrigger` to the `NODES_EXCLUDE` environment variable.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.","status":"published","published":"2026-03-27T18:06:49Z","modified":"2026-04-03T16:07:54Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:39:47.945242Z"},{"id":"GHSA-99wx-hwrx-8g4w","title":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS...","description":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page.","status":"published","published":"2026-07-01T00:34:13Z","modified":"2026-07-01T00:34:26Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"},{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/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":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:09:07.106222Z"}],"nvd":[{"id":"CVE-2026-56356","description":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page.","status":"published","published":"2026-06-30T23:17:30.997Z","modified":"2026-10-29T19:17:22.517Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/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":"medium","assessor":"secondary"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:12:27.199837Z"}],"osv":[{"id":"CVE-2026-56356","title":"n8n - Stored Cross-Site Scripting in Chat Trigger Node Custom CSS Field","description":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page.","status":"published","published":"2026-06-30T22:08:35.484Z","modified":"2026-10-31T02:30:37.866543242Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:45:11.609219Z"},{"id":"GHSA-3c7f-5hgj-h279","title":"n8n has XSS in Chat Trigger Node through Custom CSS","description":"## Impact\nAn authenticated user with permission to create or modify workflows could inject malicious JavaScript into the Custom CSS field of the Chat Trigger node. Due to a misconfiguration in the `sanitize-html` library, the sanitization could be bypassed, resulting in stored XSS on the public chat page. Any user visiting the chat URL would be affected.\n\n## Patches\nThe issue has been fixed in n8n versions 1.123.27, 2.13.3, and 2.14.1. Users should upgrade to one of these versions or later to remediate the vulnerability.\n\n## Workarounds\nIf upgrading is not immediately possible, administrators should consider the following temporary mitigations:\n- Limit workflow creation and editing permissions to fully trusted users only.\n- Disable the Chat Trigger node by adding `@n8n/n8n-nodes-langchain.chatTrigger` to the `NODES_EXCLUDE` environment variable.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.","status":"published","published":"2026-03-27T18:06:49Z","modified":"2026-07-08T08:13:08.545063543Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"},{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:46:35.406455Z"}]}}