Reading the tea leaves: given that the outage started with "connectivity issues affecting the File Manager", which was an install of Monsta FTP [1] - a commercial PHP application - I suspect the file manager got popped by one of the recently published PHP vulnerabilities, and users' FTP credentials may have been exfiltrated.
DH patched all their PHP versions extremely quickly.
hopefully their hashed/salted passwords, right? not plaintext?
20 year customer here. This morning I asked their support chatbot if this is related to the PHP vulnerabilities and it assured me that's not the case. I'm skeptical.
These status updates from the PHP incident would also have us believe that they were never directly affected: https://www.dreamhoststatus.com/pages/incident/575f0f6068263...
They're being awfully vague about this issue so far. 8 hours ago I submitted a ticket requesting more information and they've not responded yet. I guess that they're still in the thick of it.