GoFetch

GoFetch is a family of cryptographic attacks on recent Apple silicon CPUs that exploits the CPU's on-chip data memory-dependent prefetcher (DMP) to investigate the contents of memory.^[2][1] CPUs affected include the M1, M2, M3 and A14 series system-on-a-chip processors.^[1]

GoFetch

The GoFetch project logo
Date discovered	privately disclosed to Apple on 5 December 2023; 17 months ago (2023-12-05),[1] public announcement on 20 March 2024; 14 months ago (2024-03-20)[1]
Discoverer	Boru Chen, Yingchen Wang, Pradyumna Shome, Christopher W. Fletcher, David Kohlbrenner, Riccardo Paccagnella, Daniel Genkin
Affected hardware	Apple silicon CPUs (M1, M2, M3 and A14)
Website	https://gofetch.fail/

The DMP looks at cache memory content for possible pointer values, and prefetches the data at those locations into cache if it sees memory access patterns that suggest following those pointers would be useful.^[3][4] The GoFetch attacks use those speculative cache fetches to undermine a number of different cryptographic algorithms by using memory access timings to exfiltrate data from those algorithms using timing attacks.

The authors of GoFetch state that they were unable to make their exploit work on the Intel Raptor Lake processor they tested due to its more limited DMP functionality.^[1]