NaCl in 2015 allowed the CLFLUSH instruction, making rowhammer attacks possible.
- https://googleprojectzero.blogspot.com/2015/03/exploiting-dram-rowhammer-bug-to-gain.html
- https://www.exploit-db.com/exploits/36310/
- https://www.exploit-db.com/exploits/36311/
- https://github.com/9xN/xerobyte
- https://github.com/codexlynx/hardware-attacks-state-of-the-art