SLAP, Apple, and FLOP: Safari, Chrome at risk of data theft on iPhone, Mac, iPad Silicon

Many recent Apple laptops, desktops, tablets, and phones powered by Cupertino's homegrown Silicon processors can be exploited to reveal email content, browsing behavior, and other sensitive data through two newly identified side-channel attacks on Chrome and Safari. On Tuesday, security researchers Jason Kim, Jalen Chuang, and Daniel Genkin from the Georgia Institute of Technology in the US, and Yuval Yarom from Ruhr University Bochum in Germany, published papers describing two speculative-execution attacks dubbed SLAP [PDF] and FLOP [PDF]. These attacks exploit weaknesses in Apple's Arm-compatible processor designs to extract information from memory that should be off limits. In practice, that means a malicious webpage in one Chrome or Safari browser tab snooping on a page in another tab and stealing its sensitive information, such as emails being read and what have you. SLAP and FLOP build on Spectre, the 2018 microarchitecture attack that abused CPU speculation, in which processors try to accelerate operations by predicting the flow of execution through program code. By speculatively computing possible branches in logic in advance and discarding paths that aren't needed, CPUs can run applications faster. But the risk is that these speculative actions, even if discarded, can have observable side effects on shared resources – think caches or buffers – and it's these side effects that can be used by malware and rogue users to infer sensitive data, such as encryption keys, fro...