{"id":"CVE-2026-55786","published":"2026-10-14T19:17:17.777","lastModified":"2026-10-16T20:04:29.760","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.","cvssScore":8.4,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwes":["CWE-78","CWE-306"],"vendors":[],"products":[],"references":[{"url":"https://github.com/flytohub/flyto-core/commit/db7f116b1d3c5dcf94aded00d14118f81f3e225e","tags":[]},{"url":"https://github.com/flytohub/flyto-core/releases/tag/v2.26.4","tags":[]},{"url":"https://github.com/flytohub/flyto-core/security/advisories/GHSA-h9f9-h6gm-wc85","tags":[]}],"exploitRefs":[{"url":"https://github.com/flytohub/flyto-core/commit/db7f116b1d3c5dcf94aded00d14118f81f3e225e","tags":[]},{"url":"https://github.com/flytohub/flyto-core/releases/tag/v2.26.4","tags":[]},{"url":"https://github.com/flytohub/flyto-core/security/advisories/GHSA-h9f9-h6gm-wc85","tags":[]}],"hasPoc":true,"ai":null}