CVE-2026-102503
Missing Authentication on /libp2p-http Ingress in Google OSS Agent Mesh (SAM)
- State
- Published
- Severity
- 9.3 Critical
- Published
- Oct 19, 2026
- Updated
- Oct 19, 2026
- Reserved
- Sep 29, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 9.3 Critical | 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 |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
SAMGoogle |
|
References
- https://github.com/google/sam/security/advisories/GHSA-r6hp-67wp-c7jxvendor-advisory
- https://github.com/google/sam/commit/433bc99d2a2c10071167bf22acc2c930a12e64e1patch
- https://github.com/google/sam/releases/tag/v0.1.0-alpha.3release-notes
- https://github.com/google/agentmesh/security/advisories/GHSA-r6hp-67wp-c7jxexploit
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