> In early 2005, around the time that Git was written, Xiaoyun Wang, > Yiqun Lisa Yin, and Hongbo Yu announced an attack finding SHA-1 > collisions in 2^69 operations. In August they published details. > Luckily, no practical demonstrations of a collision in full SHA-1 were > published until 10 years later, in 2017.

> The hash function NewHash to replace SHA-1 should be stronger than > SHA-1 was: we would like it to be trustworthy and useful in practice > for at least 10 years.