Callback-url-file-3a-2f-2f-2fproc-2fself-2fenviron

: By injecting a malicious script into a field that ends up in the environment variables (like the HTTP_USER_AGENT ), an attacker can use LFI to include /proc/self/environ and execute that script on the server.

: The parameter name being targeted (often a URL for webhooks or link previews).

Testing for Local File Inclusion - WSTG - v4.2 | OWASP Foundation

By injecting this string, an attacker attempts to force the server to read its own environment variables, which often contain sensitive information like API keys, database credentials, or internal configuration. Understanding the Components

In the quiet hum of a server room, a single line of code arrived like a digital skeleton key. The request was disguised as a harmless callback-url

By decoding the URL-encoded characters, the payload translates to: callback-url=file:///proc/self/environ Summary of the Vulnerability