If you are not running on GCE (e.g., on-premise, AWS, or local dev), you cannot use the metadata server. Instead:
If you are developing a web feature that fetches URLs (like a link previewer or file importer), you must implement strict protections against this specific URL pattern:
When a request is made to the fetch URL http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/ , the metadata server responds with a JSON object containing information about the service accounts associated with the VM instance. The response might look similar to this:
http://google.internal indicates a critical Server-Side Request Forgery (SSRF) attempt, where attackers target the Google Cloud Metadata Server to steal service account tokens and escalate privileges. This pattern, often seen in security logs, allows unauthorized access to sensitive internal data and requires immediate remediation through input validation and network security policies. For more information, visit Google Cloud's documentation on metadata security. If you are not running on GCE (e
It looked like gibberish at first: fetch-url-http-3A-2F...
If you run curl http://metadata.google.internal from your laptop, it will fail because the DNS name resolves to a local link address only within GCP.
This article explains the purpose and usage of the metadata URL http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/ used on Google Cloud Compute Engine (GCE) instances to access instance metadata and service account credentials, and shows secure examples for common use cases. This pattern, often seen in security logs, allows
to retrieve information about a virtual machine's service accounts from the internal metadata server. Google Groups Topic: Querying Google Cloud Metadata Service Accounts Google Compute Engine Metadata Server
: Accessing this path returns a list of available service account aliases (e.g., default/ ).
curl -H "Metadata-Flavor: Google" \ http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/ Use code with caution. If you run curl http://metadata
import requests import sys
METADATA_URL = "http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/default/token" headers = "Metadata-Flavor": "Google"