{"schema":"threatline.record/2","record":{"id":"CVE-2026-103091","aliases":["GHSA-cgmg-9xf6-rrgw"],"summary":"Insecure Default Policy and Unrestricted OIDC Enrollment in Google OSS Agent Mesh (SAM)","details":"Missing Authorization (CWE-862) and Initialization of a Resource with an Insecure Default (CWE-1188) in the MCP proxy (HandleStreamPassThrough in mcp_service.go) and OIDC registration flow (GET /info and POST /register in internal/controlplane/server.go) in Google OSS Agent Mesh (SAM) versions 0.1.0-alpha.1 through 0.1.0-alpha.8 allow a remote attacker to self-enroll into the mesh and invoke arbitrary tools across all connected MCP backend nodes. Because GET /info publicly discloses OIDC configuration, POST /register auto-enrolls any valid OIDC token holder without claim filtering or ban checks, and the default policy binds sam:system:authenticated to wildcard services and targets, an attacker can obtain a mesh credential with full read, write, and execution access on backend services. Users should upgrade to version 0.1.0-alpha.9 or later, which enforces a fail-closed default policy, explicit policy-binding requirements on enrollment, and ban checks.","categories":["Unclassified"],"product":"SAM","vendor":"Google","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-103091","source_modified_at":"2026-10-19T17:44:31.625Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"SAM","vendor":"Google","versions":[{"status":"affected","version":"0.1.0-alpha.1","lessThan":"0.1.0-alpha.9","versionType":"semver"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-103091","source_modified_at":"2026-10-19T17:44:31.625Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"SAM","ecosystem":null},"version":"0.1.0-alpha.9","basis":"first unaffected version stated in the CVE record"}],"cvss":9.3,"severity":"Critical","kev":{"listed":false},"epss":{"probability":0.00496,"percentile":0.41688,"score_date":"2026-10-23"},"published_at":"2026-10-19T02:24:35.225Z","modified_at":"2026-10-19T17:44:31.625Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-103091","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T17:44:31.625Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-103091","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/google/sam/security/advisories/GHSA-cgmg-9xf6-rrgw","tags":["vendor-advisory"]},{"source":"CVE List","url":"https://github.com/google/sam/releases/tag/v0.1.0-alpha.9","tags":["release-notes"]},{"source":"CVE List","url":"https://github.com/google/agentmesh/security/advisories/GHSA-cgmg-9xf6-rrgw","tags":["exploit"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"poc","automatable":"no","technical_impact":"total","assessed_at":"2026-10-19T17:43:50.321526Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-19T17:44:31.625Z","content_hash":"ce6414e1da5817c5dd960df1640b4576656612422774ab76a7d135bff4f7bf99"}}