{"id":"CVE-2026-55786","state":"PUBLISHED","title":"Flyto2 Core: Unauthenticated Command Execution via HTTP MCP `execute_module`","description":"Flyto2 Core is an execution kernel for automation and AI-agent workflows. From 2.26.2 until 2.26.4, the HTTP MCP POST /mcp route accepts unauthenticated JSON-RPC tools/call requests and forwards execute_module arguments to the module registry without the require_auth dependency used by the REST execution routes. An unauthenticated caller can select sandbox.execute_shell and supply its command parameter, which reaches asyncio.create_subprocess_shell with the privileges of the flyto-core server process. The endpoint is reachable locally under the default loopback binding and becomes network reachable when an operator binds the server to a non-loopback interface, allowing arbitrary OS command execution and potential full host compromise. This issue is fixed in version 2.26.4.","publishedAt":"2026-10-14T18:14:39.210Z","updatedAt":"2026-10-29T13:49:14.344Z","severity":{"score":8.4,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["flytohub flyto-core"],"affected":[{"vendor":"flytohub","product":"flyto-core","versions":[{"version":">= 2.26.2, < 2.26.4","status":"affected"}]}],"references":["https://github.com/flytohub/flyto-core/security/advisories/GHSA-h9f9-h6gm-wc85","https://github.com/flytohub/flyto-core/commit/db7f116b1d3c5dcf94aded00d14118f81f3e225e","https://github.com/flytohub/flyto-core/releases/tag/v2.26.4"],"weaknesses":["CWE-78","CWE-306"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/55xxx/CVE-2026-55786.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55786","state":"PUBLISHED","datePublished":"2026-10-14T18:14:39.210Z","dateUpdated":"2026-10-29T13:49:14.344Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-17T14:40:28.380Z"},"containers":{"cna":{"title":"Flyto2 Core: Unauthenticated Command Execution via HTTP MCP `execute_module`","descriptions":[{"lang":"en","value":"Flyto2 Core is an execution kernel for automation and AI-agent workflows. From 2.26.2 until 2.26.4, the HTTP MCP POST /mcp route accepts unauthenticated JSON-RPC tools/call requests and forwards execute_module arguments to the module registry without the require_auth dependency used by the REST execution routes. An unauthenticated caller can select sandbox.execute_shell and supply its command parameter, which reaches asyncio.create_subprocess_shell with the privileges of the flyto-core server process. The endpoint is reachable locally under the default loopback binding and becomes network reachable when an operator binds the server to a non-loopback interface, allowing arbitrary OS command execution and potential full host compromise. This issue is fixed in version 2.26.4."}],"affected":[{"vendor":"flytohub","product":"flyto-core","versions":[{"version":">= 2.26.2, < 2.26.4","status":"affected"}]}],"references":[{"url":"https://github.com/flytohub/flyto-core/security/advisories/GHSA-h9f9-h6gm-wc85","name":"https://github.com/flytohub/flyto-core/security/advisories/GHSA-h9f9-h6gm-wc85","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/flytohub/flyto-core/commit/db7f116b1d3c5dcf94aded00d14118f81f3e225e","name":"https://github.com/flytohub/flyto-core/commit/db7f116b1d3c5dcf94aded00d14118f81f3e225e","tags":["x_refsource_MISC"]},{"url":"https://github.com/flytohub/flyto-core/releases/tag/v2.26.4","name":"https://github.com/flytohub/flyto-core/releases/tag/v2.26.4","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"LOCAL","availabilityImpact":"HIGH","baseScore":8.4,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-78","lang":"en","description":"CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-306","lang":"en","description":"CWE-306: Missing Authentication for Critical Function","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-14T18:14:39.210Z"},"source":{"advisory":"GHSA-h9f9-h6gm-wc85","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/flytohub/flyto-core/security/advisories/GHSA-h9f9-h6gm-wc85","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-29T13:49:05.403752Z","id":"CVE-2026-55786","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-29T13:49:14.344Z"}}]}}}