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
I’m not a security expert, but password hashing is mostly to slow down someone from getting all the passwords. You can’t reverse the hash, but you can generate hashes until you find a match. When hashing, you can dial in how much compute it would take someone to try and solve all the hashes in your database. If you used a good password, it will be more difficult to solve your hashed password. But it’s best to change your password as Plex suggests.
So it depends on how secure a password is and how strong of hashing Plex used when storing the hashed passwords. I have no idea if this is like a “this will take a year” or “this will take a billion years” to solve all the hashes. More compute also means you can solve the hashes faster. Maybe someone with a security background could chime in.
If they are following best practices then individual hashes should be salted and the database of hashes should be peppered so even if someone brute forces an offline copy of the hashes they wouldn’t result in actual useable passwords.
I don’t think that’s how salts work. I might be wrong, but I think it works like this
Password + Salt -> Hash
Notice how those 3 users use the same password, but the different salts results in 3 different hashes. That doesn’t make it any harder to crack a single hash, but it means I have to crack the same password 3 times. It just slows down password cracking.
Edit: my explanation isn’t wrong, but I didn’t understand the pepper part until now. So I understand the above now.
You missed the part about pepper. Pepper is something that's added, like salt, but that isn't stored with the password. A low security version of this is an environment variable, but it could also be a secure hardware device on the machine.
So it's more like this:
If an attacker only has the salt, they'll "crack" the password into something that's not the original password:
brute_force("higbskjf", "hakf") - > "kdrnskk". The idea is that it might take a few days for the attacker to recognize the error, and by then the security team has already responded and locked the backdoor.Even if the passwords are peppered, users should assume their password is compromised and change them. But peppering may prevent a cascade effect from reused passwords.
I actually didn’t realize pepper was a thing. I mostly do frontend. But that’s really interesting!
That’s all you can do though, extend the time it takes to brute force, so I’m not sure what the distinction being made is.
I thought you were suggesting that salted hashed passwords were uncrackable but maybe I misunderstood this
Edit: I understand the offline pepper part now. My bad
Gotcha, no, I wasn’t trying to make that claim, it’s just a way to make it more difficult/time consuming
Response time is critical. It's the difference between immediately getting pwned vs. having time for the security team to identify the threat, notify their users, and users to assess the impact of the breach and change their passwords.