{"id":"CVE-2026-102503","title":"Missing Authentication on /libp2p-http Ingress in Google OSS Agent Mesh (SAM)","summary":"Missing Authentication for Critical Function (CWE-306) and Missing Authorization (CWE-862) in the /libp2p-http ingress server (StartIngressServer in cmd/sam-node/node.go) in Google OSS Agent Mesh (SAM) versions 0.1.0-alpha.1 through 0.1.…","severity":"critical","cvss":9.3,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","cvssSource":"cna","cwe":["CWE-306","CWE-862"],"vendor":"Google","product":"github.com/google/sam","affected":["github.com/google/sam >= 0.1.0-alpha.1 < 0.1.0-alpha.3"],"published":"2026-10-19","updated":"2026-10-19","sourceUpdated":"2026-10-19T02:20:35.753Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-102503","references":[{"url":"https://github.com/google/sam/security/advisories/GHSA-r6hp-67wp-c7jx"},{"url":"https://github.com/google/sam/commit/433bc99d2a2c10071167bf22acc2c930a12e64e1"},{"url":"https://github.com/google/sam/releases/tag/v0.1.0-alpha.3"}],"tags":["cve.org"],"ingestedAt":"2026-10-19T02:58:59.958Z","slug":"CVE-2026-102503","body":"## Overview\n\nMissing Authentication for Critical Function (CWE-306) and Missing Authorization (CWE-862) in the /libp2p-http ingress server (StartIngressServer in cmd/sam-node/node.go) in Google OSS Agent Mesh (SAM) versions 0.1.0-alpha.1 through 0.1.0-alpha.2 allow an unauthenticated remote libp2p peer to bypass Biscuit capability policy enforcement and invoke arbitrary registered backend services (including command/stdio-backed MCP servers, A2A, and inference endpoints). While the MCP protocol stream handler enforces WithBiscuitAuth and Authorize checks, the parallel /libp2p-http ingress routes requests directly to backend service handlers without verifying a Biscuit token or mesh enrollment. Users should upgrade to version 0.1.0-alpha.3 or later.\n\n## Affected\n\n- `github.com/google/sam >= 0.1.0-alpha.1 < 0.1.0-alpha.3`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":51,"depthScoreParts":{"impact":51.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}