{"api_version":"1","generated_at":"2026-09-19T17:24:09+00:00","cve":"CVE-2026-55887","urls":{"html":"https://cve.report/CVE-2026-55887","api":"https://cve.report/api/cve/CVE-2026-55887.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-55887","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55887"},"summary":{"title":"MCP Gateway: Argument injection via OCI image label YAML in Docker MCP Gateway","description":"MCP Gateway allows easy and secure running and deployment of MCP servers. From 0.21.0 until 0.42.2, Docker MCP Gateway YAML-unmarshalled the attacker-controlled io.docker.server.metadata OCI image label into the broad catalog.Server structure for direct docker:// references and catalog snapshot imports in pkg/oci/self_contained.go and pkg/workingset/workingset.go. Runtime-shaping fields including Volumes, User, and ExtraHosts were then appended to the docker run argument vector without an origin allowlist, allowing a malicious image author to request host filesystem or Docker socket mounts and UID 0 execution when a victim selected or pulled the image. This container-creation-time boundary bypass can execute arbitrary code on the host and is not prevented by no-new-privileges because no in-container privilege escalation is required. 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