Get the backstory on the Hash Seed guessing game and HashWick from Fedor Indutny:

About one year ago, I’ve discovered a way to do a Denial-of-Service (DoS) attack on a local Node.js instance. The process involved sending huge amounts of data to the HTTP server running on the same machine as the attacker, and measuring the timing differences between various payloads. Given that the scope of attack was limited to the same machine, it was decided by V8 team and myself that the issue wasn’t worth looking in yet. Nevertheless, a blog post was published.

This year, I had a chance to revisit the Hash Seed guessing game with restored enthusiasm and new ideas. The results of this experiment are murky, and no fix is available yet in V8. Thus all V8 release lines are vulnerable to the HashWick attack.

Fedor also mentioned that this issue was disclosed responsibly and this blog post was published 90+ days after the initial report.