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Linux Kernel Exploit Busily Rooting 64-Bit Machines
An anonymous reader writes "Running 64-bit Linux? Haven't updated yet? You're probably being rooted as I type this. CVE-2010-3081, this week's second high-profile local root exploit in the Linux kernel, is compromising machines left and right. Almost all 64-bit machines are affected, and 'Ac1db1tch3z' (classy) published code to let any local user get a root shell. Ac1db1tch3z's exploit is more malicious than usual because it leaves a backdoor behind for itself to exploit later even if the hole is patched. Luckily, there's a tool you can run to see if you've already been exploited, courtesy of security company Ksplice, which beat most of the Linux vendors with a 'rebootless' version of the patch."
I thought only windows got exploited this way.... oh thats right All OS's do.
Why does the summary and articles read like a paid advertisement for Ksplice?
Yes, there's an available rights escalation vulnerability in recent Linux Kernels that's best patched by updating your system with the latest updates. The breathless nature of the fine summary betrays an eagerness to get Linux admins to click the links before they've done so. I'd rather not. Social engineering is such a powerful exploit mechanism after all.
The Windows geeks obviously will want to paint this as a native Linux vulnerability that they don't have - and it is marginally true. That's fine - but it's an escalation bug, not a remote root, and they've several dozen remote root bugs to close before they point fingers.
Help stamp out iliturcy.
This is a local exploit so I'm not horribly concerned and here is why.
You should always treat your systems as if an exploit already exists for both remote and local connections.
The systems I maintain are part of a bit of an elaborate network. There is a huge investment in controlling incoming and outgoing traffic as well as managing who actually has access to systems. While a local exploit a big deal it's not like there are a great number of places for users to inject this code. If someone could compromise an input vector and piggyback the exploit that still wouldn't get them very far. In fact, without knowing key details regarding the network infrastructure they would simply nab a host that could not reach the outside world.
With that said we do have a bit of reliance on lbs, traffic inspection, firewalls and a good bit of monitoring equipment. However, there is a solid investment in specific purpose network and security protocols to accomplish these goals. In a bit of a cheaper shop I'm wondering what others do to maintain security and get some of the same tools. (I'm being very vague about our setup intentionally, but there have to be some decent foss network tools as well).
If hostile users have local access, you're pretty much boned anyway.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Now Ksplice is really starting to piss me off. This is at least the fifth time we've get this kind of crap on slashdot.
Besides that, this is an escalation vuln ... it's local, ok? Not a remote exploit. And, regardless of all that, there's already a fix, which was promptly released before this got out of hand.
So, between the ksplice assholes that abuse each vulnerability that is published to blow it out of proportion and somehow imply that if you require ksplice to patch this without loosing your job (I mean, come on, If your service is critical enough that it can't accept 2 minutes of downtime for a reboot, then you have redundancy and can update machines one by one without any real downtime) ; and the winslow assholes that don't understand shit about security and somehow think that this means that GNU/Linux is insecure and as bad as their shitty system, I'm going nuts every time there is a new vuln in the kernel.
WTF am I doing replying to an AC at 5 A.M on a Friday night?
Am I the only person who says "hell no" to running that "diagnosis" program? After looking through the code real quick, I have no interest whatsoever in running a program that performs the very exploit I'm supposed to be scared of, cuz I don't have time to make sure ksplite neutralized it properly. Also, since it's only a local exploit, I'm not concerned enough about it to run a diagnosis tool that implements it.
And good lord god almighty, what 12 year old wrote this code, that they think having function names like put_your_hands_up_hooker() makes them cool?
There is something to be said though about going to a 64bit operating system. The fact that there are a little more than twice as many general purpose registers in the CPU available means that code can be compiled to not need to do memory fetches anywhere near as often which means that the code will run faster. the extra addressing space has always been a red herring argument (e.g. i only need it if i have more than 4gb of ram).
A virus scanner isn't going to do much against a rootkit.
C'mon now. As others have pointed out, and has been mentioned earlier on /., this is a local root exploit. It's bad, it affects a lot of users (in theory), but to write this is to simply spread fear for most of those using Linux.
Why? Because the systems that inexperienced users run also happen to be those with a few, generally trusted users. Think netbooks. Sure, all local root exploits are bad and should be patched asap. But that doesn't mean "you're probably being rooted as I type this". It means that a remote attacker needs user-level privileges (say, with a browser or plugin vulnerability) first. Since Ubuntu and probably other major distros have already patched this, and the default settings for updates on these systems is to check fairly frequently, most end users will have the patched kernel quickly.
That leaves multi-user systems. The admins of these servers certainly benefit from finding out about the vulnerability asap, and they did (including through previous stories here). By now, though, most admins should have something in place if they don't have full trust in their users. If they don't, they should definitely be looking at whether this was exploited.
The bottom line is that there are many local root exploits which come out every year. This is the latest one, with a patch already available. Responsible admins of multi-user systems are used to dealing with this, and home users are almost certainly going to be patched before it causes any issues. For them, the latest Flash vulnerability is more worrisome. Even the extremely rare remote exploit of a service isn't usually an issue, since most modern distros don't start much of anything by default (including ssh, IIRC).
"The universe seems neither benign nor hostile, merely indifferent." --Carl Sagan
Point out a current remote root exploit in Windows. To the best of my knowledge, there are none. Which means that the original poster is just fluffing his feathers trying to divert attention from the Linux issue.
While this isn't something that means Linux is majorly insecure or anything, it is a Linux issue. However fanboys don't like that, they can't just say "Yep, there's a problem." Instead they want to try and deflect it, make it about something else. So he deflects the issue by claiming there are some nebulous "remote root bugs," without any specifics.
Our UNIX admin has the philosophy that anyone with local access can get root if they want it bad enough. Security isn't done by presuming you've made that impossible. Rather security is done by making sure you don't give access to just anyone, and to monitoring what people do. Local escalation exploits are things to be fixed, since they can always make a remote exploit worse (someone exploits something remotely, gets unprivileged access, exploits the local exploit to get root) they aren't a critical threat usually.
However I will say you don't make things much better when you start with name calling with regards to Windows and the people that run it. That smacks of being the sort of asshole that knows little about the other platform that you are painting them to be. That you have a preferred platform is great. One would hope it is based on good reasons. However name calling on another platform indicates it is more likely based on zealotry than anything else.
Tell us how great OSS is.
Tell us how much better Linux is.
Tell us how badly Microsoft sucks.
I'm a PC, and using Windows instead of Linux was my idea.
I knew it was just a matter of time before Ballmer showed up as an AC on Slashdot.
As a long time user I get the option to disable advertising. I don't. I even whitelist Slashdot in Adblock because I support the site and the banner ads are rarely obnoxious.
These poorly disguised articles-as-ads are quite annoying though. Just make KSplice pay for a banner like everyone else.
Y'know, sometimes there are posts that are poignant, interesting, on-topic, and yet are modded down as a troll for no better reason than people who have mod points are more interested in squelching challenging ideas. That's fine, and slashdot has a mechanism to deal with that, called Karma.
Because I have good /. Karma I can call your attention to the parent post even though I believe it's been badly moderated. Because I'm a Slashdot subscriber, I get an extra point to add to this post, which calls attention to the parent. I have enough good Karma that even if this post is moderated a troll I will have lost nothing.
I'm making this amplifying post because the parent post was moderated down in one second. It was born silenced. Obviously there were moderators prepared to prevent you from hearing my response to the question asked. Some of you might for this reason alone find my words above meaningful or intriguing.
Help stamp out iliturcy.
Would you kids get off my lawn?
Me too. Let's see Microsoft get a patch out that fast. ;)
Yeah really fast 2+ years!
What exactly is the point of supplying a checksum by the same route/download method as the file in question? Surely if the file can be modified, so can the checksum. Maybe it would be useful if people got the checksum and verified it was the same checksum everyone else saw, then verified the file with it, but that just doesn't happen.
For a home user, not a big deal. For an business environment, much more so. Dismissing it as 'nothing to see' is shortsighted at best, especially when considering the backdoor left by the hack.