CVE-2026-32871

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"defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-pipeline-runtime-minimal-cpu-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-pipeline-runtime-pytorch-cuda-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-pipeline-runtime-pytorch-llmcompressor-cuda-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift 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"https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-datascience-cpu-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-minimal-cpu-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-minimal-cuda-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-minimal-rocm-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-pytorch-cuda-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-pytorch-llmcompressor-cuda-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-pytorch-rocm-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-tensorflow-cuda-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-tensorflow-rocm-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:openshift_ai"], "vendor": "Red Hat", "product": "Red Hat OpenShift AI (RHOAI)", "packageName": "rhoai/odh-workbench-jupyter-trustyai-cpu-py312-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}]}], "published": "2026-04-02T15:16:38.740", "references": [{"url": "https://github.com/PrefectHQ/fastmcp/commit/40bdfb6b1de0ce30609ee9ba5bb95ecd04a9fb71", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/PrefectHQ/fastmcp/pull/3507", "tags": ["Issue Tracking", "Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/PrefectHQ/fastmcp/releases/tag/v3.2.0", "tags": ["Product", "Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/PrefectHQ/fastmcp/security/advisories/GHSA-vv7q-7jx5-f767", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:36350", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-32871", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2454434", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://github.com/PrefectHQ/fastmcp/security/advisories/GHSA-vv7q-7jx5-f767", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32871.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-918"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-918"}]}], "descriptions": [{"lang": "en", "value": "FastMCP is a Pythonic way to build MCP servers and clients. Prior to version 3.2.0, the OpenAPIProvider in FastMCP exposes internal APIs to MCP clients by parsing OpenAPI specifications. The RequestDirector class is responsible for constructing HTTP requests to the backend service. A vulnerability exists in the _build_url() method. When an OpenAPI operation defines path parameters (e.g., /api/v1/users/{user_id}), the system directly substitutes parameter values into the URL template string without URL-encoding. Subsequently, urllib.parse.urljoin() resolves the final URL. Since urljoin() interprets ../ sequences as directory traversal, an attacker controlling a path parameter can perform path traversal attacks to escape the intended API prefix and access arbitrary backend endpoints. This results in authenticated SSRF, as requests are sent with the authorization headers configured in the MCP provider. This issue has been patched in version 3.2.0."}, {"lang": "es", "value": "FastMCP es una forma Pythonic de construir servidores y clientes MCP. Antes de la versi\u00f3n 3.2.0, el OpenAPIProvider en FastMCP expone APIs internas a clientes MCP al analizar especificaciones OpenAPI. La clase RequestDirector es responsable de construir solicitudes HTTP al servicio de backend. Existe una vulnerabilidad en el m\u00e9todo _build_url(). Cuando una operaci\u00f3n OpenAPI define par\u00e1metros de ruta (p. ej., /api/v1/users/{user_id}), el sistema sustituye directamente los valores de los par\u00e1metros en la cadena de la plantilla URL sin codificaci\u00f3n URL. Posteriormente, urllib.parse.urljoin() resuelve la URL final. Dado que urljoin() interpreta las secuencias .. / como salto de directorio, un atacante que controla un par\u00e1metro de ruta puede realizar ataques de salto de ruta para escapar del prefijo de API previsto y acceder a puntos finales de backend arbitrarios. Esto resulta en SSRF autenticado, ya que las solicitudes se env\u00edan con los encabezados de autorizaci\u00f3n configurados en el proveedor MCP. Este problema ha sido parcheado en la versi\u00f3n 3.2.0."}], "lastModified": "2026-10-26T21:10:00.170", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:jlowin:fastmcp:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4247F36F-7D37-47DF-A475-E607F1BAD799", "versionEndExcluding": "3.2.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}