# Hardware Vulnerability in Apple’s M-Series Chips
**Summary:**
A new hardware vulnerability has been discovered in Apple’s M-series chips, allowing hackers to extract secret encryption keys. The vulnerability is related to the chips’ data memory-dependent prefetcher, which predicts memory addresses and can confuse memory content with pointer values, leaking data through a side channel. The attack, named GoFetch, can extract various encryption keys in a relatively short amount of time. Exploiting the vulnerability requires running a malicious app on the target computer, making it a serious threat.
## Details of the Vulnerability
The vulnerability resides in the chips’ data memory-dependent prefetcher, which reduces latency between main memory and the CPU by predicting memory addresses of data that running code is likely to access. The prefetcher can confuse memory content with pointer values, leading to the leakage of data through a side channel. This behavior is a violation of the constant-time paradigm and can be exploited by a malicious app to extract secret encryption keys.
## The GoFetch Attack
The GoFetch attack, as it has been named, uses an application that doesn’t require root access and can run with the same user privileges as most third-party applications on a macOS system. By running on the same performance cluster as the targeted cryptography app, GoFetch can mine enough secrets to leak a secret key. The attack works against both classical encryption algorithms and newer encryption hardened against quantum computer attacks.
## Impact and Extraction Times
The GoFetch app can extract a 2048-bit RSA key in less than an hour, a 2048-bit Diffie-Hellman key in a little over two hours, and other encryption keys in varying times. The attack extracts the app secret key while feeding inputs to the targeted app, eliminating the need for the targeted app to perform cryptographic operations during the collection period.
## Mitigation and Patching
Exploiting the vulnerability requires running a malicious app on the target computer, limiting its impact to some extent. However, like many hardware side-channel attacks, this vulnerability is unpatchable, making it a persistent threat to Apple’s M-series chips.
## Key Points
– The vulnerability in Apple’s M-series chips allows hackers to extract secret encryption keys.
– The GoFetch attack exploits the chips’ data memory-dependent prefetcher to leak data through a side channel.
– The attack can extract various encryption keys in a relatively short amount of time.
– Exploiting the vulnerability requires running a malicious app on the target computer.
– The vulnerability is unpatchable, posing a long-term threat to Apple’s M-series chips.