Browser Feature

CORB Leaks

October 1, 2020

Cross-Origin Read Blocking (CORB) is a web platform security feature aimed at reducing the impact of speculative side-channel attacks such as Spectre. Unfortunately, blocking certain types of requests introduced a new type of XS-Leaks 1 that allows attackers to detect if CORB was enforced on one request, but wasn’t on another. Nevertheless, the introduced XS-Leaks are much less problematic than the issues actively protected by CORB (e.g. Spectre). info This is a known issue in Chromium, and while it might remain unfixed, its impact is greatly reduced by the rollout of SameSite Cookies by default in Chromium-based browsers. ...

CORP Leaks

October 1, 2020

Explanation # Cross-Origin Resource Policy (CORP) is a web platform security feature that allows websites to prevent certain resources from being loaded by other origins. This protection complements CORB since it is an opt-in defense, whereas CORB blocks some cross-origin reads by default. Unfortunately, similar to CORB, applications can introduce a new XS-Leak if they misconfigure the use of this protection. A webpage will introduce an XS-Leak if CORP is enforced based on user data. ...