Golang
[AD REMOVED]
CONNECT method
In the Go programming language, a common practice when handling HTTP requests, specifically using the net/http library, is the automatic conversion of the request path into a standardized format. This process involves:
- Paths ending with a slash (
/) like/flag/are redirected to their non-slash counterpart,/flag. - Paths containing directory traversal sequences such as
/../flagare simplified and redirected to/flag. - Paths with a trailing period as in
/flag/.are also redirected to the clean path/flag.
However, an exception is observed with the use of the CONNECT method. Unlike other HTTP methods, CONNECT does not trigger the path normalization process. This behavior opens a potential avenue for accessing protected resources. By employing the CONNECT method alongside the --path-as-is option in curl, one can bypass the standard path normalization and potentially reach restricted areas.
The following command demonstrates how to exploit this behavior:
[AD REMOVED]