I also received a version of one of these emails a couple of days ago, which contained a correct password.
However, I may be able to add a couple of details which could be mildly informative.
Email address - I use unique email addresses for each site I create an account for. This email address was used for MySpace (a site I probably haven't logged into for nearly 15 years!).
Password - a very old, insecure password (8 alphanumeric non-random characters) I foolishly re-used on a few 'low risk' websites - before I reassessed my security habits.
Data breach - paraphrased from wikipedia:
In May 2016, the data for almost 360 million MySpace accounts was offered on a dark market website. The leaked data included email addresses, usernames and weakly encrypted passwords. The exact data breach date is unknown, but analysis of the data suggests it was exposed eight years before being made public, in approximately 2008.
Other data breaches are also undoubtedly being used for these emails.
Am I worried by this particular email? No.
But this does demonstrate the importance of following current very basic security advice (use unique, strong passwords on all accounts). That's the very minimum - also consider multi-factor authentication and other strategies.
Personally I highly recommend using a reputable password manager to more easily achieve better online security.
