Note

This information is based off of early reports I have seen. I don’t claim to know the extent to which any damage was done and as such recommend a password reset (two-factor authentication would not be of use if authentication tokens were compromised), but we do know that this was a Javascript injection.

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With the recent Lemmy.world incident, I’d like to update you all. This vulnerability could not have affected you had you been using only Memmy while browsing. It was a Javascript injection, and as Memmy does not execute any Javascript, there is no attack surface here.

The only case where this could have affected you would be if you had been signed in to your account inside of the in-app browser or the default browser and opened one of these posts. That however would not be something with Memmy itself, but rather the accessing of the PWA.

Regardless, as we don’t actually know what happened, I’d recommend changing passwords. If any JWTs were compromised during this, regardless of 2FA status these tokens could be used to authenticate with your account.

From what I have seen, this was an issue that was limited to Lemmy.world, as supposedly they were running a custom frontend build. Other than that, I don’t know anything else.

Also, for the record, there is only one instance in this application where a webview is used, which is when viewing the terms of service which simply loads a local file from the app assets.

Any questions, I’ll try to answer them but you’d be better off asking people more knowledgeable about the incident.

As always, this is a good time to go over your online security practices.

It is strongly recommended that you use a password manager such as Bitwarden or 1Password if you do not use one already. This can help prevent credential surfing if you have used the same password over many sites, preventing you from having several of your accounts breached from a single breach.

If you have used a password on Lemmy.world that you have used on other sites, you should change those other sites passwords immediately.

Email addresses may have been breached during the attack and this may result in increased spam and phishing emails. It is strongly advised that you throughly verify any emails that you receive after this, particularly ones relating to login requests, messages from banks or payment providers, such as PayPal or government institutions.

Thank you for using Memmy and stay safe!

    • gkd@lemmy.mlOPM
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      1 year ago

      I don’t have an answer to that. Lemmy.world is offline and lemmy.blahaj.zone is currently displaying a broken YouTube video. Other than that, I know nothing besides the chatter going on in the Lemmy Matrix.

  • Evoke3626@lemmy.fmhy.ml
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    1 year ago

    I feel really stupid but how do you sign out of the app? I also cannot find create a new password like one user said under profile settings

    • NotSteve_@beehaw.org
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      1 year ago

      I think to sign out you have to go to manage accounts and delete your account. The wording is a bit scary but it’s just removing your user from memmy. The only issue (it might have just been me) is that the add account button wasn’t working, so when I did this I had to reinstall the app to log back in.

  • Mic_Check_One_Two@reddthat.com
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    1 year ago

    Just wanted to note that some things may be broken due to the invalid JWTs?

    I started getting “Not logged in” errors shortly after the JWT reset. I assume because the app was still using the old (now invalid) JWTs. I tried clearing my cache, so the app would request a new (valid) JWT. I’m still getting the error on my lemmy.world accounts.

    Next, I decided to try deleting the accounts from my app entirely. But when I try to disable the Push Notifications option prior to deleting, the app freezes on an infinite loading screen.

    It may not be a huge issue since the Push Notifications are probably using the old JWTs. But wanted to point it out, since others may be dealing with the same thing.

    • gkd@lemmy.mlOPM
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      1 year ago

      Oh I had push notifications offline during the whole incident. Let me put them back up.

  • b3nsn0w@pricefield.org
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    1 year ago

    XSS was not the primary attack vector, it was just used to deface the site. Given what lemmy.world looks like right now, and how lemmy.blahaj.zone looked like without JS before the admins took back control, it is evident that the hackers were able to take control of the site on a database level. The magnitude and nature of changes are extremely unlikely to have been possible through the Lemmy API.

    Password hashes are extremely likely to have been stolen, but luckily Lemmy has sane password storage practices (bcrypt at a difficulty setting of 12) so if your password is decently strong, it’s incredibly unlikely to be compromised. Still, changing it is a good idea.

    Furthermore, the site’s JWT secret is stored in the database, so worrying about tokens is futile, the hackers can generate new ones on-demand. This will be the instances’ jobs to sort out after they have taken back control.

    • DrQuint@lemmy.ml
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      1 year ago

      Changing password is a good idea.

      Changing it NOW is a bad one tho, we don’t know what’s going on on .world’s side.

      Unless of course, if we’re talking about changing any other sites that use the same password, at which point: One, do that. Two, stop using the same password on more than one site. Time to get a password manager.

      • gkd@lemmy.mlOPM
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        1 year ago

        Yea, the JWTs were invalidated and then the Al compromised admin account posted saying “hack fixed”. Huge red flag that there’s more access going on than we are aware of.

    • gkd@lemmy.mlOPM
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      1 year ago

      Yes this is correct. It seems that more info has been coming in and frankly now with the super suspicious activity going on at .world, I’d say it’s safe to at least consider there’s a lot more going on.

  • Klanky@sopuli.xyz
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    1 year ago

    I’m going to assume that since my account is on a different instance I’m good for now. I interact with a few lemmy.world communities but just posts/comments.