« We recommend that SHA-1 based signatures should be marked as unsafe much sooner than prescribed by current international policy. Even though freestart collisions do not directly lead to actual collisions for SHA-1, in our case, the experimental data we obtained in the process enable significantly more accurate projections on the real-world cost of actual collisions for SHA-1, compared to previous projections. Concretely, we estimate the SHA-1 collision cost today (i.e., Fall 2015) between 75K$ and 120K$ renting Amazon EC2 cloud computing over a few months. By contrast, security expert Bruce Schneier previously projected (based on calculations from Jesse Walker) the SHA-1 collision cost to be ~173K$ by 2018. Note that he deems this to be within the resources of a criminal syndicate. Large corporations and governments may possess even greater resources and may not require Amazon EC2. Microsoft, Google and Mozilla have all announced that their respective browsers will stop accepting SHA-1 based SSL certificates by 2017 (and that SHA-1-based certificates should not be issued after 2015). »
Via Aeris (
https://blog.imirhil.fr/)