SSRF Sheriff – A Simple SSRF-testing Sheriff Written In Go

This is an SSRF testing sheriff written in Go. It was originally created for the Uber H1-4420 2019 London Live Hacking Event, but it is now being open-sourced for other organizations to implement and contribute back to.

Features

• Repsond to any HTTP method (GET, POST, PUT, DELETE, etc.)
• Configurable secret token (see base.example.yaml)
• Content-specific responses
  • With secret token in response body
    • JSON
    • XML
    • HTML
    • CSV
    • TXT
  • Without token in response body
    • GIF
    • PNG
    • JPEG
    • MP3
    • MP4

Usage

go get github.com/teknogeek/ssrf-sheriff
cd $GOPATH/src/github.com/teknogeek/ssrf-sheriff
cp config/base.example.yaml config/base.yaml

# ... configure ...

go run main.go

Example Requests:
Plaintext

$ curl -sSD- http://127.0.0.1:8000/foobar
HTTP/1.1 200 OK
Content-Type: text/plain
X-Secret-Token: SUP3R_S3cret_1337_K3y
Date: Mon, 14 Oct 2019 16:37:36 GMT
Content-Length: 21

SUP3R_S3cret_1337_K3y

XML

$ curl -sSD- http://127.0.0.1:8000/foobar.xml
HTTP/1.1 200 OK
Content-Type: application/xml
X-Secret-Token: SUP3R_S3cret_1337_K3y
Date: Mon, 14 Oct 2019 16:37:41 GMT
Content-Length: 81

<SerializableResponse><token>SUP3R_S3cret_1337_K3y</token></SerializableResponse>

TODO

• Dynamically generate valid responses with the secret token visible for
  • GIF
  • PNG
  • JPEG
  • MP3
  • MP4
• Secrets in HTTP response generated/created/signed per-request, instead of returning a single secret for all requests
• TLS support

Credit
Inspired (and requested) by Frans Rosén during his talk at BountyCon ’19 Singapore