{"id":"CVE-2026-58057","aliases":["EUVD-2026-39977","GHSA-rqqr-m697-6jq3"],"status":"published","title":"Flowise - Custom MCP Environment Variable Denylist Bypass via Case Sensitivity","description":"Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.","severity":{"version":"4.0","score":2.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.01556,"percentile":0.75539,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":false},"cwes":["CWE-178"],"published":"2026-06-28T01:32:58Z","modified":"2026-11-09T02:47:16Z","exploits":[{"source":"exploitdb","id":"EDB-52623","title":"Flowise  3.1.3 - arbitrary code execution","type":"webapps","platform":"multiple","date":"2026-07-07","url":"https://www.exploit-db.com/exploits/52623"},{"source":"pocgithub","id":"CerberusMrXi/Flowise-CVE-2026-58057-exploit","title":"CerberusMrXi/Flowise-CVE-2026-58057-exploit","date":"2026-07-23","url":"https://github.com/CerberusMrXi/Flowise-CVE-2026-58057-exploit"}],"products":[{"vendor":"flowise","product":"flowise"},{"vendor":"flowiseai","product":"flowise"}],"references":[{"url":"https://github.com/bikini/exploitarium/tree/main/flowise-mcp-env-case-bypass-poc","tags":["exploit","third-party-advisory","Exploit","Third Party Advisory","evidence"]},{"url":"https://github.com/FlowiseAI/Flowise/pull/6471","tags":["issue-tracking","patch","Issue Tracking","Patch","fix"]},{"url":"https://www.vulncheck.com/advisories/flowise-custom-mcp-environment-variable-denylist-bypass-via-case-sensitivity","tags":["third-party-advisory","Exploit","Patch","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58057","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-rqqr-m697-6jq3"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58057.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-58057","title":"Flowise - Custom MCP Environment Variable Denylist Bypass via Case Sensitivity","description":"Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.","status":"published","published":"2026-06-28T01:32:58.594Z","modified":"2026-11-08T14:06:43.889Z","cvss":[{"version":"4.0","score":2.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N","level":"low","assessor":"cna"},{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-178"],"updated_at":"2026-11-08T15:43:33.322657Z"}],"euvd":[{"id":"EUVD-2026-39977","description":"Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.","status":"published","published":"2026-06-28T01:32:58Z","modified":"2026-11-08T14:06:43Z","cvss":[{"version":"4.0","score":2.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N","level":"low"}],"updated_at":"2026-11-08T15:13:07.762611Z"}],"ghsa":[{"id":"GHSA-rqqr-m697-6jq3","title":"Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a...","description":"Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.","status":"published","published":"2026-06-28T03:33:40Z","modified":"2026-06-28T03:33:41Z","cvss":[{"version":"4.0","score":2.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/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":"low"},{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium"}],"cwes":["CWE-178"],"updated_at":"2026-11-02T15:09:02.633671Z"}],"nvd":[{"id":"CVE-2026-58057","description":"Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.","status":"published","published":"2026-06-28T02:16:32.99Z","modified":"2026-10-25T17:10:00.197Z","cvss":[{"version":"4.0","score":2.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/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":"low","assessor":"secondary"},{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"secondary"}],"cwes":["CWE-178"],"updated_at":"2026-11-02T14:12:26.508751Z"}],"osv":[{"id":"CVE-2026-58057","title":"Flowise - Custom MCP Environment Variable Denylist Bypass via Case Sensitivity","description":"Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.","status":"published","published":"2026-06-28T01:32:58.594Z","modified":"2026-11-09T02:47:16.006420328Z","cvss":[{"version":"4.0","score":2.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N","level":"low"}],"cwes":["CWE-178"],"updated_at":"2026-11-09T03:16:24.800471Z"}]}}