{"id":"CVE-2026-53957","summary":"Contentful MCP Server: export_space/import_space tools pass LLM-controlled `host`/`proxy` args to CMA client, redirecting server PAT to attacker-controlled endpoint","details":"Contentful MCP Server is a Model Context Protocol server for the Contentful Management API. Prior to @contentful/mcp-server 1.7.19 and @contentful/mcp-tools 0.4.5, export_space and import_space in packages/mcp-tools/src/tools/jobs/space-to-space-migration/exportSpace.ts and packages/mcp-tools/src/tools/jobs/space-to-space-migration/importSpace.ts expose host, proxy, rawProxy, and insecure network options to LLM-controlled tool arguments and combine those options with the server's CONTENTFUL_MANAGEMENT_TOKEN. After space_to_space_migration_handler enables the migration tools, a direct MCP call or prompt injection through attacker-controlled Contentful content can redirect Contentful Management API requests and their Authorization header to an attacker-controlled host or proxy. The regular tools that use createToolClient are unaffected because those tools pin the host from server configuration. Exposure of the personal access token permits persistent out-of-band access to every Contentful space within the token's scope. This issue is fixed in @contentful/mcp-server 1.7.19 and @contentful/mcp-tools 0.4.5.","aliases":["GHSA-2xhg-73j7-rrgx"],"modified":"2026-09-18T03:30:59.537955471Z","published":"2026-09-15T14:34:53.699Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53957.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-918"]},"references":[{"type":"WEB","url":"https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-server@1.7.19"},{"type":"WEB","url":"https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-tools@0.4.5"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53957.json"},{"type":"ADVISORY","url":"https://github.com/contentful/contentful-mcp-server/security/advisories/GHSA-2xhg-73j7-rrgx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53957"},{"type":"FIX","url":"https://github.com/contentful/contentful-mcp-server/commit/fa7477ee48515f4248bc91a025eab0ca83423fe0"},{"type":"FIX","url":"https://github.com/contentful/contentful-mcp-server/pull/376"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/contentful/contentful-mcp-server","events":[{"introduced":"0"},{"fixed":"fa7477ee48515f4248bc91a025eab0ca83423fe0"},{"fixed":"ce904443ae38dfeaeadf305591c95b800e782570"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"1.7.19"},{"fixed":"0.4.5"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["mcp-tools@0.4.4","mcp-server@1.7.18","mcp-tools@0.4.3","mcp-server@1.7.17","mcp-tools@0.4.2","mcp-server@1.7.16","mcp-tools@0.4.1","mcp-server@1.7.15","mcp-tools@0.4.0","mcp-server@1.7.14","mcp-tools@0.3.2","mcp-server@1.7.13","mcp-tools@0.3.1","mcp-server@1.7.12","mcp-tools@0.3.0","mcp-server@1.7.11","mcp-tools@0.2.6","mcp-server@1.7.10","mcp-tools@0.2.5","mcp-server@1.7.9","mcp-tools@0.2.4","mcp-server@1.7.8","mcp-tools@0.2.3","mcp-server@1.7.7","mcp-server@1.7.6","mcp-tools@0.2.2","mcp-server@1.7.5","mcp-tools@0.2.1","mcp-server@1.7.4","mcp-tools@0.2.0","mcp-server@1.7.3","mcp-tools@0.1.2","mcp-server@1.7.2","mcp-tools@0.1.1","mcp-server@1.7.1","mcp-tools@0.1.0","mcp-server@1.7.0","v1.6.2","v1.6.1","v1.6.0","v1.5.0","v1.4.0","v1.3.0","v1.2.2","v1.2.1","v1.2.0","v1.1.0","v1.0.5","v1.0.4","v1.0.3","v1.0.2","v1.0.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53957.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N"}]}