- cross-posted to:
- linux@lemmy.ml
- hackernews@lemmy.bestiver.se
- cross-posted to:
- linux@lemmy.ml
- hackernews@lemmy.bestiver.se
are you affected?
- is your sshd running on musl? (alpine, openwrt, buildroot, yocto)
- is it not using pam? alpine’s openssh-server doesn’t by default, or maybe you set UsePAM no
- are password logins still on? they are by default
- is there an account with just * as its password? key-only users, ldap users, root on alpine
- and some other account with a real password?
- then that * account takes any password between 257 and 1024 characters
on alpine’s official aws and azure images that’s the default alpine user, and it has passwordless doas. so it’s root
on debian, ubuntu, fedora or anything else with glibc? going through pam? dropbear? openbsd? you’re fine
I mean, not that it’s not severe, but which container images have ssh baked in? If you’re using good stripped down images, you’re fine here.
Not sure where the overlap is between"ssh is enabled" and “one of those OSes”. LXCs maybe?
SSH enabled and the SSH port of the container accessible and it’s set for password auth.
And there’s an account in the container that has a password set. That’s already a security problem on its own.
Maybe something like git forges and gist alternatives?
They use key based authentication
I wonder if Forgejo / Gitea instances are vulnerable
Good Point! I’ll check if my forgejo container has password auth enabled. :D It’s LAN only though.
Remember, password-auth off is the problematic setting.
No you’re wrong. Stop dramatizing and spreading false info. From your link:
Prerequisites: Are password logins still on?
You can’t trigger this if password auth is disabled.
Ah. Thanks for the correction. The intro + where I originally learned this from made me overreact a bit, it seems.
Linux phones? PostmarketOS is alpine-based. And a lot of people may ssh to their phone.
checked on my phone, there are a few system users with
!*as their password, from what i can tell!blocks all logins and is not bypassed by this exploit, but their shell is set to/sbin/nologinanyways.The default firewall rules of nura block ssh from mobile data, so only wifi and usb connections would be affected if at all.
Everyone should disable ssh password auth anyways, using the phones often short pin for ssh is not secure.
Most Android apps that make a ssh server use dropbear afaik.
Nura (formerly PostmarketOS) is not Android.
I expect it’s a common trend though, people generally use Dropbear on embedded devices for the same reasons they prefer Alpine, it’s more compact.
I used to run SFTPGO in a container as a NAS type service. Their default image is based on Debian, but they offer Alpine versions. Password authentication is enabled by default.
Even if there is ssh it probably is going to be dropbear and it is unlikely that password based authentication would be enabled