Lemmy.world (and some others) were hacked
While I was asleep, apparently the site was hacked. Luckily, (big) part of the lemmy.world team is in US, and some early birds in EU also helped mitigate this.
As I am told, this was the issue:
- There is an vulnerability which was exploited
- Several people had their JWT cookies leaked, including at least one admin
- Attackers started changing site settings and posting fake announcements etc
Our mitigations:
- We removed the vulnerability
- Deleted all comments and private messages that contained the exploit
- Rotated JWT secret which invalidated all existing cookies
The vulnerability will be fixed by the Lemmy devs.
Details of the vulnerability are here
Many thanks for all that helped, and sorry for any inconvenience caused!
Update While we believe the admins accounts were what they were after, it could be that other users accounts were compromised. Your cookie could have been 'stolen' and the hacker could have had access to your account, creating posts and comments under your name, and accessing/changing your settings (which shows your e-mail).
For this, you would have had to be using lemmy.world at that time, and load a page that had the vulnerability in it.
Good thing we all use randomly generated passwords for every account and always remember to change them every few months.
Passwords are safe, it's temporary session tokens (already invalidated) that were exposed.
Good call.
However, that wouldn't have prevented this from happening. Not even MFA can protect you in case of an exploit like this.
My password is 4, it was randomly generated with a dice. Every few months I roll the dice again.
I'm not perfect as far as password opsec goes, but I did indeed use a randomly generated unique password here.
Hell, even if your password safe is only what's built into Firefox or Chrome, that's still better than using easy-to-guess passwords or sharing passwords.
And randomly generated emails! (Thanks to SimpleLogin!)
Brave has a really good random password generator logged in and a password manager that is protected by a 24 character seed phrase