前幾天在 Hacker News 上看到目前撞 SHA-1 collision 的難度：「How easy is it in 2022 to find a SHA1 collision? (stackexchange.com)」，原文在「How easy is it in 2022 to find a SHA1 collision?」。
在答案裡面有提到，即使在不考慮 ASIC 的情況下，光是用 GPU 算就可以可以降到 ~5.4 GPU years 了：
Remarkably, we can see that in only 5 years, we're down from an attack costing ~110 GPU years to an attack costing ~8 GPU-years in 2020 (thanks to theoretical improvements & newer GPUs) to just ~5.4 GPU years nowadays (thanks to newer, faster GPUs).
除了演算法本身的進步以外，GPU 的效能進展也帶動不少，而如果考慮到 ASIC 的話會快更多，對美國政府來說，如果搬出超級電腦來算的話，就是一天可以撞一個出來：
In a more realistic way, it would take less than a day to do it on a super-computer such as the one owned by the US Department of Energy's Oak Ridge National Laboratory (ORNL) named "Summit".
沒有在追進度，發現進展蠻快的，現在的攻擊速度比想像中快不少...
