RIP is required for client-side inflation error side-channel mitigation #182
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It is possible to detect redirections using fetch using the same technique of client-side inflation errors. For example, on Chrome: `await fetch(`https://bank.com/redir#<BIG-fragment>`, {method: 'GET', mode :'no-cors', credentials: 'include'});` The server redirects to `/bigger` based on a cookie which is included in the fetch request. The first request succeeds, but the second request (redirection) will raise an exception which an attacker can observe.
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It is possible to detect redirections using
fetchwith the same technique as presented in "client-side inflation errors."Example:
await fetch("https://target.com/redir#<BIG-fragment>", {method: 'GET', mode :'no-cors', credentials: 'include'});If the server redirects to an endpoint bigger than
/redirwhen there is a cookie attached to the request, the first request succeeds, but the second request (redirection) will raise an exception which can be observed. Provided thatlength(URL + #<BIG-fragment>) = (URL size limit - 1)Works on Chrome (2MB URL size limit) and Firefox (1MB URL size limit).
These requests are rejected by the RIP.