CVE-2026-53957
Contentful MCP Server: export_space/import_space tools pass LLM-controlled `host`/`proxy` args to CMA client, redirecting server PAT to attacker-controlled endpoint
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | @contentful/mcp-server | < 1.7.19 | 1.7.19 |
| npm | @contentful/mcp-tools | < 0.4.5 | 0.4.5 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-2xhg-73j7-rrgx
- https://github.com/contentful/contentful-mcp-server/security/advisories/GHSA-2xhg-73j7-rrgx
- https://github.com/contentful/contentful-mcp-server/pull/376
- https://github.com/contentful/contentful-mcp-server/commit/fa7477ee48515f4248bc91a025eab0ca83423fe0
- https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-server%401.7.19
- https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-tools%400.4.5
- https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-server@1.7.19
- https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-tools@0.4.5