Vulnerability · Published Sep 15, 2026 · Assigned by GitHub_M
CVE-2026-53957Contentful MCP Server: export_space/import_space tools pass LLM-controlled `host`/`proxy` args to CMA client, redirecting server PAT to attacker-controlled endpoint
High 7.7
In plain English
A high-severity server-side request forgery in contentful-mcp-server from contentful. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @contentful/mcp-server | 1.7.19 | GHSA-2xhg-73j7-rrgx |
| npm | @contentful/mcp-tools | 0.4.5 | GHSA-2xhg-73j7-rrgx |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| contentful | contentful-mcp-server | < 1.7.19 |
| @contentful | mcp-server | < 1.7.19 |
| @contentful | mcp-tools | < 0.4.5 |
Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
References
- https://github.com/contentful/contentful-mcp-server/security/advisories/GHSA-2xhg-73j7-rrgx x_refsource_CONFIRM
- https://github.com/contentful/contentful-mcp-server/pull/376 x_refsource_MISC
- https://github.com/contentful/contentful-mcp-server/commit/fa7477ee48515f4248bc91a025eab0ca83423fe0 x_refsource_MISC
- https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-server@1.7.19 x_refsource_MISC
- https://github.com/contentful/contentful-mcp-server/releases/tag/mcp-tools@0.4.5 x_refsource_MISC