CVE-2026-55786: high-severity vulnerability in flytohub flyto-core
Flyto2 Core: Unauthenticated Command Execution via HTTP MCP `execute_module`
Published · Updated
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43Vexday Risk Score
Prioritize patching. It exploitation observed by VulnCheck.
ssvc Actcvss 8.4epss 0.4%
from disclosure to weapon
Published on NVDOct 14
VulnCheckSep 14
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.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
flytohub · flyto-coreRelated CVEs — flytohub flyto-core
In the same product, most dangerous first.
CVE-2026-67429CRITICALFlyto2 Core: Arbitrary file write via image.download (and other file-writing modules)EPSS 0.6%CVE-2026-67427HIGHFlyto2 Core: ${env.VAR} interpolation reads any env secret despite env.get being denylistedEPSS 0.4%CVE-2026-73530MEDIUMFlyto2 Core < 2.28.0 SSRF Guard Bypass via is_private_ip()EPSS 0.4%CVE-2026-67428HIGHFlyto2 Core: Multiple HTTP-family modules fetch client-controlled URLs without the SSRF guard their siblings apply (SSRF to internal/metadata)EPSS 0.4%CVE-2026-67425HIGHFlyto2 Core: LLM/API keys leak to an attacker-controlled base_urlEPSS 0.4%CVE-2026-67426CRITICALFlyto2 Core: Unauthenticated flyto-verification /run: callback_url SSRF and internal runner-secret exfiltrationEPSS 0.4%