CVE-2026-102503

CriticalCVSS 9.3

Published: 19/10/2026(UTC)Translated: 19/10/2026(UTC)NVD NIST

Summary

Google OSS Agent Mesh (SAM) versions 0.1.0-alpha.1 through 0.1.0-alpha.2 contain Missing Authentication for Critical Function (CWE-306) and Missing Authorization (CWE-862) in the /libp2p-http ingress server. An unauthenticated remote libp2p peer can bypass Biscuit capability policy enforcement and invoke arbitrary registered backend services, including command/stdio-backed MCP servers, A2A, and inference endpoints.

Risk Assessment

An unauthenticated attacker can invoke critical backend services, potentially leading to unauthorized data access and command execution.

Recommendation

Upgrade Google OSS Agent Mesh to version 0.1.0-alpha.3 or later.

Other vulnerabilities in Google OSS Agent Mesh (SAM)

CVE-2026-103091Critical
Google OSS Agent Mesh (SAM) versions 0.1.0-alpha.1 through 0.1.0-alpha.8 contain Missing Authorization (CWE-862) and Insecure Default Initialization (CWE-1188) in the MCP proxy and OIDC registration flow. Public disclosure of OIDC configuration via GET /info and auto-enrollment of any valid OIDC token holder via POST /register without claim filtering or ban checks allow a remote attacker to self-enroll into the mesh and invoke arbitrary tools across all connected MCP backend nodes.

Original NVD description (English source)

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 0.1.0-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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS