As far as I can tell, they had stale dns records pointing at IPs that were eventually used to run scammy web servers. I couldn't find any connection to a breac

As far as I can tell, they had stale dns records pointing at IPs that were eventually used to run scammy web servers. I couldn't find any connection to a breach. The author does correctly point out that the CSP headers were overly permissive. If the new owners of the IPs knew what they had, they could definitely have used that to find other flaws and exploit them. I think this situation would need to be combined with XSS on an active Houseparty domain to be effective. The weak CSP would make XSS or CSRF possible. Edit: if authentication tokens were stored in cookies that span subdomains, it's also possible sessions could be leaked that way.