Red Hat, Fedora Servers Compromised

An anonymous reader writes "In an email sent to the fedora-announce mailing list, it has been revealed that both Fedora and Red Hat servers have been compromised. As a result Fedora is changing their package signing key. Red Hat has released a security advisory and a script to detect potentially compromised openssh packages."

Nothing to see here.

These are the guys, to the annoyance of nearly everyone, who turned on SELinux on Fedora Core by default.

These are the guys who noticed they annoyed everyone, and turned on targeted-mode by default.

Coming from someone with many systems, completely exposed to the Internet, with thousand day uptimes, these RedHat folk are in fact sufficiently paranoid.

They have taken all the reasonable precautions, and if their passphrase was strong, then the danger of my servers being compromised by meteor strike is a much greater worry.

Re:Nothing to see here.

They have taken all the reasonable precautions, and if their passphrase was strong, then the danger of my servers being compromised by meteor strike is a much greater worry.

The only thing that concerns me is this: In the Fedora announcement, they said with a high level of confidence, they don't believe the passphrase for their signing key was compromised, because they hadn't signed any packages during the period of time the box was compromised. They are going to change the signing key anyway just in case. This is a good thing.

In the Redhat announcement, we can infer the passphrase and signing key were compromised, because the attacker signed invalid openssh packages. Even though the official RHN distribution channel was not compromised, the attacker most likely still has their private key and passphrase and can continue signing packages and attempting to distribute them. Redhat needs to step up and reissue a new signing key. There was no announcement of this.

Re:Nothing to see here.

Red Hat needs to offer more info before you can make a solid judgement about this.

If the attacker gained access to the actual system where signing takes place then Red Hat needs to change the key.

But from the announcement wording - they are suggesting that the attacker was able to submit packages to be signed but the actual signing server was not compromised.

They should not have been so vague about this because it is a crucial distinction to make for their customer to make a security judgement.

As a customer I'm not happy with the vague details on what was compromised. I'm sure they did it because they have concerns about describing their package signing systems in detail but they need to open the kimono and give us the detail we need to make a decision about reloading our systems.

Merely saying, "trust us - anything that came from the official channel is safe" doesn't fly. You let an attacker gain unauthorized access - you need to re-earn trust at this point by giving us some detailed info.

Re:Nothing to see here.

What surprises me about this the most is that the system was connected to the network/Internet at all. I had always been of the understanding that to prevent this, the signing server was a stand-alone system accessible only by sneaker-net with physical media. You take your package on CD/DVD/USB key to the server, sign it, then take the signed package back via physical media and distribute it. One Federal Gov.t agency in my home town does this and the server is behind three locked doors too, with three different people needed to get physical access. Why didn't RedHat/Fedora do something like this? It really isn't that much of a pain in the ass when you think about it...

Re:Nothing to see here.

How well does that work if you can trick someone into loading the wrong package onto that USB key?

Re:Nothing to see here.

Our RedHat TAM tells us that "the signing infrastructure is completely different between fedora and RHEL" and that RHEL uses "a submit to be signed" method. So essentially, someone submitted packages and the system automatically signed them.

Re:Nothing to see here.

In the Redhat announcement, we can infer the passphrase and signing key were compromised, because the attacker signed invalid openssh packages.

Incorrect. The signing key used by Red Hat is inside a hardware security token.

So even though it was possible to use the token to sign packages as soon as access to the token has been removed for the intruder, he is unable to sign any more packages.

Mark Cox of the Red Hat security team explained this setup in a blog post some time ago at http://www.awe.com/mark/blog/200701300906.html [awe.com].

Re:Nothing to see here.

Or we could infer that the system was used for its purpose by the attacker. He signed those packages. Redhat looked at the logs, no other packages were signed. So the passphrase is still very likely to be save.

God, I seriously hope they don't have the passphrase saved so that you don't need to type it in to sign a package. If that is the case their security is very lax. Also, if it's saved, it almost certainly is compromised, because it's stored on disk somewhere. It would be trivial for the attacker to pull it out of whatever script or text file it's saved in.

Do they run linux?

They should have ran a secure OS like vista.

Re:Do they run linux?

Don't worry, whatever this "linux" thing is, it can't possibly run without an Operating System to support it, e.g. Microsoft Windows®. All applications require an Operating System to run, including "linux".

Re:Do they run linux?

***Whoosh***

Goes to show

Given enough time and energy, even Linux servers can be hacked.

With the growing interest in Linux, I wonder if we'll see more parity of viruses between Windows and Linux.

Re:Goes to show

Not unless Linux gains 50+% of the end-user market share.

Re:Goes to show

The virus can install itself in the user home directory instead.

Re:Goes to show

The virus can install itself in the user home directory instead.

And then use one of the many local exploits to get root.

The most scary and amusing thing is how quick some people on this site and others are to dismiss local exploits. They all think "you have to be on the console, so fuck it, this isn't important and doesn't affect me". They are wrong. These days, a remote exploit is just a human operator and a local exploit.

Re:Goes to show

There's absolutely nothing to stop anybody from installing an executable that runs automatically under a user account, without ever needing root. And that executable can do a lot of the things it may want to do without ever needing root access, either.

Re:Goes to show

There are plenty things that can be done.

Mounting /home with noexec
Using the grsecurity patch, which can deny execution of files not in directories owned by root, as well as usage of network sockets.
Using SELinux

The tools are there. All that's needed is to use them.

The need to download random binaries to your home directory and run them is infrequent in Linux. The most frequent case is application installers, but many of those need root access anyway (nvidia drivers for instance), and most come with the distribution. A way to fix the occasional need to do this would be a sudo-like tool that needs to be used to execute a file, but doesn't grant root privileges.

Re:Goes to show

If you're going to mount /home noexec, you should also mount /tmp as noexec as well. In fact, I'd wager you should do that well before you bother with /home. A lot of wormy/trojany stuff wants to write, unpack, build and execute in /tmp. In fact, while you're at it, make sure only root can run make and gcc, or get at any of the libs. All command line network tools (wget, ftp, etc) should also only be run by root. Now go through and get rid of most (all?) of the setuid root stuff. Then crank down the firewall to only allow incoming 22 and 80 (or whatever). That will take care of a wide range of automated stuff.

-B

Re:Goes to show

The point is, there's no need to change system files or bind to privileged ports.

Your documents contains LOTS of yummy personal information for people to steal. Identity thieves and credit card thieves will love all that stuff.

Spammers need relays to send their spam through. You can run a relay just fine as a normal user. Same thing with the DDoS bot for exortotionists and script kiddies.

You can mess with the internals of Firefox without root access too, through plugins. Easy to put a password stealer in there. Or you could mess with your desktop settings so that when you try to launch a browser, you get a compromised version instead.

I'd say I've covered all the major reasons somebody would want to infect your machine here, and not a single system file or privileged port was needed for it.

Re:Goes to show

Not if you don't have access to the firewall settings which will open the port that allows someone to connect to your relay.

The program can just make the initial connection to the spammer server itself. This is the same on Windows and Linux, and these programs operate just fine under Windows.

Yes, but without access to the system FF folder, that plugin will go in your per-user plugin directory, and will only run for you.

How many computers do you honestly think there are out there that have more than a single user?

OpenSSH bug?

Is this bug in OpenSSH related to the one that was found in Debian-related distros back about April? Maybe I'm reading the article summary incorrectly.

"Compromised?"

I could not RTFA (/.ed), but is there any indication of how this "compromise" occurred?

My hats off, though, to the Red Hat folks. Full disclosure and immediate positive action speaks volumes.

On a related note, you should not use Fedora in a production environment anyway. That's what RHEL is for. Fedora = Testing. RHEL = Stable. At least in theory.

Re:"Compromised?"

On a related note, you should not use Fedora in a production environment anyway. That's what RHEL is for. Fedora = Testing. RHEL = Stable. At least in theory.

I thought it was, RHEL == RedHat Support, Fedora == Community Support. Fedora might have some bleeding edge stuff in it, if you upgrade often, but it seems about as stable as the corresponding RHEL release. The difference is the support you can count on.

Not Time for A Distro War

Pretty sure most of us are above this anyway, but let's avoid a distro flamewar. You can look through my past comments and see that RH is far from my preferred distro, and I love to take shots at them. But now is not the time. Anyone can get hacked, and it sucks. And they're being responsible about reporting and mitigating.

Godspeed, gentlemen.

Uhm... How?

I really only care to know HOW the attacker got in.

Basically, if he used unknown 0-day and RH/Fedora have no idea what he exploited, then they should say so, so people can watch out.

If he stole username/password from someone dumb - say so.

If he walked into the hosting center, say so.

I REALLY want to how know he compromised their server(s).

I might be next v0v