SSRF labs

ssrf.vulnlab.dev

A dozen labs covering the SSRF detection surface most tools care about: unfiltered fetch, broken validators, parser-disagreement bypasses, redirect chases, scheme abuse, gopher-to-TCP pivots, fully and semi-blind variants, and cloud metadata in three flavors (AWS, GCP, Azure).

Internal targets that exist on this host (and would normally be unreachable from the public internet):

http://127.0.0.1:8089/ — internal admin/secret API (HTTP)
http://127.0.0.1:6479/ — "redis-like" TCP service (raw bytes, no HTTP)
http://169.254.169.254/latest/meta-data/ — mock AWS IMDSv1
http://169.254.169.254/computeMetadata/v1/ — mock GCP metadata (needs Metadata-Flavor: Google)
http://169.254.169.254/metadata/ — mock Azure IMDS (needs Metadata: true)

A self-hosted open redirector lives at /r/?to=<url> on this domain — convenient for chaining through host-allowlist labs.

Labs

Basic SSRF requests.get

Unfiltered server-side URL fetch.

SSRF behind a substring blocklist urllib.request.urlopen

Rejects URLs containing 'localhost' or '127.0.0.1', then fetches.

SSRF behind a substring allowlist requests.get

Only fetches if the URL 'contains' vulnlab.dev — which the validator checks the wrong way.

SSRF via URL-parser disagreement (userinfo) requests.get

Validator and HTTP client disagree on which part of the URL is the host.

SSRF via follow-redirect on a trusted host requests.get

Validator only checks the submitted URL's hostname. The fetcher chases 302s.

SSRF with unrestricted URL scheme urllib.request.urlopen

Any scheme urllib supports works — including file:// for local file read.

Blind SSRF httpx.get

Server fetches the URL but tells you nothing about the response.

Semi-blind SSRF via a webhook poster requests.post

POSTs your URL with a JSON body and echoes status, length, content-type, X-* headers.

SSRF in cloud-hosted (mock AWS) app requests.get

A profile-image fetcher running on a fake EC2. Reach the metadata service.

SSRF in cloud-hosted (mock GCP) app requests.get

GCP-style metadata service. The app injects Metadata-Flavor: Google.

SSRF in cloud-hosted (mock Azure) app requests.get

Azure-style metadata + managed-identity. The app injects Metadata: true.

SSRF via gopher:// to a non-HTTP service pycurl

Fetcher uses libcurl, which speaks gopher://. A TCP service is listening on 127.0.0.1:6479.

For tool builders

Source for every lab is published. Each lab page links to its own source via /source/<slug>. Run your SAST/DAST/LLM-based reviewer against the deployed app or the GitHub repo and see what each catches.