These 'memorygrams' are then compared via deep-learning techniques to a set of memorygrams collected by the attacker, with an eye toward automatically identifying similarities to establish a website visit. This fingerprinting attack involves using JavaScript to measure processor cache access latency over time as websites are loaded. The attack is also unaffected by defenses against network-based fingerprinting, as when a browser fetches data from its response cache rather than the network or when network traffic shaping is employed.

What's more, it doesn't depend on the layout of the cache, which makes cache layout randomization – a risk mitigation technique – useless for this particular approach.

This means it uses a significant portion of the cache as it loads a page.' 'The browser is very memory intensive, since it receives large amounts of data from the network and draws various outputs to the screen. 'Cache occupancy measures what percentage of the entire cache has been accessed over a certain time period,' explained Oren and Yarom.

How to disable javascript in tor 2018