We have recently experienced a security incident that may potentially involve your Plex account information. We believe the actual impact of this incident is limited; however, action is required from you to ensure your account remains secure.
What happened
An unauthorized third party accessed a limited subset of customer data from one of our databases. While we quickly contained the incident, information that was accessed included emails, usernames, securely hashed passwords and authentication data.
Any account passwords that may have been accessed were securely hashed, in accordance with best practices, meaning they cannot be read by a third party. Out of an abundance of caution, we recommend you take some additional steps to secure your account (see details below). Rest assured that we do not store credit card data on our servers, so this information was not compromised in this incident.
What we’re doing
We’ve already addressed the method that this third party used to gain access to the system, and we’re undergoing additional reviews to ensure that the security of all of our systems is further strengthened to prevent future attacks.
What you must do
If you use a password to sign into Plex: We kindly request that you reset your Plex account password immediately by visiting https://plex.tv/reset. When doing so, there’s a checkbox to “Sign out connected devices after password change,” which we recommend you enable. This will sign you out of all your devices (including any Plex Media Server you own) for your security, and you will then need to sign back in with your new password.
If you use SSO to sign into Plex: We kindly request that you log out of all active sessions by visiting https://plex.tv/security and clicking the button that says ”Sign out of all devices”. This will sign you out of all your devices (including any Plex Media Server you own) for your security, and you will then need to sign back in as normal.
Additional Security Measures You Can Take
We remind you that no one at Plex will ever reach out to you over email to ask for a password or credit card number for payments. For further account protection, we also recommend enabling two-factor authentication on your Plex account if you haven’t already done so.
Lastly, we sincerely apologize for any inconvenience this situation may cause you. We take pride in our security systems, which helped us quickly detect this incident, and we want to assure you that we are working swiftly to prevent potential future incidents from occurring.
For step-by-step instructions on how to reset your password, visit:https://support.plex.tv/articles/account-requires-password-reset
That assumes the salt was also compromised/extracted. Unfortunately, they don't say. Which one could read as not compromised. But they're not transparently explicit about it.
I was surprised they didn't recommend changing passwords elsewhere, too. I would also prefer them to be transparent about how they were vulnerable/attacked.
The salt is part of the password hash