[schwag09]

This article briefly mentions a very useful analysis tool for NGINX configuration: Gixy.

It looks for the following misconfigurations[0]:

  - [ssrf] Server Side Request Forgery
  - [http_splitting] HTTP Splitting
  - [origins] Problems with referrer/origin validation
  - [add_header_redefinition] Redefining of response headers by "add_header" directive
  - [host_spoofing] Request's Host header forgery
  - [valid_referers] none in valid_referers
  - [add_header_multiline] Multiline response headers
  - [alias_traversal] Path traversal via misconfigured alias

The alias traversal gotcha is one of the most pernicious I've seen. A single, seemingly innocuous '/' is the difference between a path traversal vulnerability or not.

[0]: https://github.com/yandex/gixy#what-it-can-do