More on the story here: https://www.vice.com/en/article/v7m9jx/credit-card-hacking-forum-gets-hacked-exposing-300000-hackers-accounts

We have an expert comment from Ilia Kolochenko at ImmuniWeb:

“Most of the compromised accounts have fake data and IPs from anonymous VPNs or proxies that are not likely to bring much actionable evidence to law enforcement agencies for investigation. Even the Western law enforcement agencies are currently underequipped to investigate and prosecute cybercrime on a large scale, and will probably not initiate investigatory operations after the leak."

"On the other hand, private messages – if also stolen – can be a treasure trove: many beginners carelessly expose sensitive technical, personal and other details there. Even a simple analysis of the unencrypted messages can paint a broad picture of the underground marketplace and shed light on the true identities of wrongdoers and their clients. Cybercriminals will probably not exploit the stolen information in an aggressive manner except for some rival gangs aiming to stiff competition."

"It would be interesting to learn about the origins of the hack, but mostly it will have stemmed from a 0day in forum web software, compromised admin’s machine or maybe even a password reuse attack. We will probably not get a forensic report and may just observe how the situation develops.”

About Ilia N. Kolochenko, Founder and Chief Architect, ImmuniWeb SA

• Master of Legal Studies (Washington University in St. Louis, School of Law)
• Master of Science in Criminal Justice, Cybercrime Investigation (Boston University)
• Doctoral Student at Capitol Technology University (PhD in Cybersecurity Leadership)
• Forbes Technology Council Member 

Ilia is a Swiss application security expert and entrepreneur. Starting his career as a penetration tester, and after serving in the Swiss artillery, he founded his first pen-testing and cybersecurity consulting company High-Tech Bridge in 2008. The penetration testing boutique was later named a leading service provider in the European market by Frost & Sullivan in 2012. To take traditional penetration testing to the next level, Ilia invented Multilayer Application Security Testing Technology that is now embodied at ImmuniWeb® AI Platform which he leads as Chief Architect. Serving customers from highly regulated industries in over 50 countries today, ImmuniWeb has a growing number of prestigious awards and industry recognition from Gartner, Forrester, IDC and Frost & Sullivan for the practical usage of AI and Machine Learning. ImmuniWeb Community Edition has over 100,000 daily tests.