{"cve":"CVE-2026-55887","nvd":{"published":"2026-09-15T16:17:16.667","modified":"2026-09-30T17:51:56.193","status":"Deferred","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. This issue is fixed in version 0.42.2.","cvss_v4":{"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H","score":8.7},"cvss_v3":null,"cwes":["CWE-88"],"references":["https://github.com/docker/mcp-gateway/commit/306d2d94a3b526f43281313321bf784f2d46a7fe","https://github.com/docker/mcp-gateway/commit/439b2200d9e26a4ff414aeb043785df45a78422b","https://github.com/docker/mcp-gateway/pull/498","https://github.com/docker/mcp-gateway/releases/tag/v0.42.2","https://github.com/docker/mcp-gateway/security/advisories/GHSA-r2xf-7jw5-pjg6"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-55887","score":0.00222,"percentile":0.12686,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-r2xf-7jw5-pjg6","url":"https://osv.dev/vulnerability/GHSA-r2xf-7jw5-pjg6","summary":"Docker MCP Gateway: Argument injection via OCI image label YAML","modified":"2026-06-25T23:11:30.259315636Z","packages":[{"ecosystem":"Go","name":"github.com/docker/mcp-gateway","purl":"pkg:golang/github.com/docker/mcp-gateway","ranges":[">=0.21.0 <0.42.2"],"fixed":["0.42.2"]}]},{"id":"GO-2026-5604","url":"https://osv.dev/vulnerability/GO-2026-5604","summary":"Docker MCP Gateway: Argument injection via OCI image label YAML in github.com/docker/mcp-gateway","modified":"2026-06-25T23:01:35.593583277Z","packages":[{"ecosystem":"Go","name":"github.com/docker/mcp-gateway","purl":"pkg:golang/github.com/docker/mcp-gateway","ranges":[">=0.21.0 <0.42.2"],"fixed":["0.42.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}