Reverse Proxy Misconfigurations · passage 7 of 9

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2 code blocks · Reverse Proxy Misconfigurations/README.md

For testing systems you own or are authorised to test, and for defending them. Nothing here is run by this page.

Nginx matches incoming request URIs against the location blocks defined in your configuration. * `location /app/` matches requests to `/app/`, `/app/foo`, `/app/bar/123`, etc. * `location /app` (no trailing slash) matches `/app*` (i.e., `/application`, `/appfile`, etc.), This means in Nginx, the presence or absence of a slash in a location block changes the matching logic.

server {
  location /app/ {
    # Handles /app/ and anything below, e.g., /app/foo
  }
  location /app {
    # Handles only /app with nothing after OR routes like /application, /appzzz
  }
}

Example of a vulnerable configuration: An attacker requesting `/styles../secret.txt` resolves to `/path/styles/../secret.txt`

location /styles {
  alias /path/css/;
}

Every one of the 9 is a mark on the map. Named now: 1 to 9, reading order first.

Zoom in on the map and the dots under the middle of it are named where they are.

Data as of 2026-11-15. CVE List through 2026-11-15 · EPSS of 2026-11-14 · CISA KEV checked 2026-11-15. Source: PayloadsAllTheThings by Swissky and contributors, MIT License. For authorised testing only.