In fact, it can be worst. I just take some check on Ubuntu Crash Reporting and I found this.
Bug reports about crashes which are automatically generated by the
Apport system are now private by default. This avoids exposing
potentially sensitive data like passwords to the public. Those bug
reports are now inspected by a trusted Ubuntu developer before marking
it public.
There is no indication which version(s) is/are affected. IMHO, to prevent password leak, you should either upgrade Apport or disabled it.
This issue is documented/highlight under Apport wiki
Apport collects potentially sensitive data, such as core dumps, stack traces, and log files. They can contain passwords, credit card
numbers, serial numbers, and other private material.
(update)
This issue need further scrutinize, because there are confusion of ecryptfs and login passphrase vs mount passphrase.