you are underestimating the severity of the bug. The bug leaks server memory - in which case unencrypted passwords are being sent to the server by the user's browser in order to be hashed to be compared to the hashed versions in storage.

Normally this is protected by tls, but as you can see, for servers that suffer from this hole, it's as good as naught.

Note that this occurs for "any" connections hitting the vulnerable server, meaning that the patient attacker can just run this in a script and scoop up passwords, credit card #'s, form information POST'ed in by all users of the web service all day long until the hole is closed. and even then there's a good chance that the private keys were already exposed, in which case the attacker can now masquerade as the server.