Botnet Worm Targets DSL Modems and Routers
CoreDuo writes "The people who bring you the DroneBL DNS Blacklist services, while investigating an ongoing DDoS incident, have discovered a botnet composed of exploited DSL modems and routers. OpenWRT/DD-WRT devices all appear to be vulnerable. What makes this worm impressive is the sophisticated nature of the bot, and the potential damage it can do not only to an unknowing end user, but to small businesses using non-commercial Internet connections, and to the unknowing public taking advantage of free Wi-Fi services. The botnet is believed to have infected 100,000 hosts." A followup to the article notes that the bot's IRC control channel now claims that it has been shut down, though the ongoing DDoS attack on DroneBL suggests otherwise.
Glad I recently switched my router to Tomato. Works better than DD-WRT, too.
It is no measure of health to be well adjusted to a profoundly sick society. - Krishnamurti
based?
But I thought too hard and lost the opportunity. I wear the AC hat with shame.
Don't forget, Tomatoes get worms too!
I actually RTFA, logged into my router, and I'm still not sure what to look for to see if we've been compromised.
What exactly are we looking for?
first post!
-edfardos
Was the best movie of all time.
A. How do we know whether our kit is vulnerable?
B. How to tell whether we are infected?
C. What to do about it if we are?
I'd guess most people, even geeks, just think of their router as a black box and don't know much about them as long as they keep on working.
The problem, more than linux based, is if have fixed/easy/guessable user/password for it to get into. And if well you could be responsible for that kind of info, what if is not your router/dsl modem, but from the company that gives you connectivity? What if they weren't so creative with the password of the device?
Not a big deal, you can just:
ssh to your router
ifconfig eth0 down
All fixed, not vulnerable anymore.
Okay, now this is scary.
Folks having OpenWRT/DD-WRT are usually a bit more savvy that the average user, so to see something specifically targeting such users is surprising.
And the fact it's gone this long without being noticed is even MORE frightening.
[End Of Line]
Configure the device for IPv6, over a tunnel or whatever. The worm blocks your control ports using iptables, but not apparently ip6tables.
Who has their router set to allow access to the admin interface from the wan side? This is certainly not done by default. Is there some sort of browser hijack involved with this to gain access to the inside of the network?
The subject text box isn't the "write-the-beginning-of-the-message-until-space-runs-out-and-then-use-the-big-textarea-under-it" field. The big textarea under it is there for a clear reason.
Just sayin'.
Ok, TFA states
Get a shell on the vulnerable device (methods vary).
How will this supposed worm manage to login to the box? Brute force? Properly configured Linux will block login attempts for quite a while after several failures. SSH? Can't be compromised within a reasonable time. Telnet? Not supported on all routers I know.
The article doesn't go into the essential details, so I call FUD until proven otherwise.
Want to hear the voice of GOD? cat
I commented on this exact subject about 18 months ago. Amused to see the security industry finally catching up.
Every mans' island needs an ocean; choose your ocean carefully.
... administer your home router over the Internet? Who does that? If you don't have an open port, even on these boxen, how could you be attacked?
But, it seems to me that this is more likely an attack on stock Linksys boxen that re-flashes with a special DD-WRT designed to "phone home." Yes, DD-WRT/OpenWRT are also vulnerable if they have weak passwords, but the bulk is more likely the former.
(Disclaimer: My home router runs HyperWRT & is not listed in DroneBL.)
anks. Boy that reply really helped me out! You're right. This way is much better because now you have to view the post to figure out that what I'm writing is unimportant. By the way, what is that "tell parent poster to bite me" check box all about? I'm just askin.
I'm glad I saw this story. Even though I'd been using a fairly strong password, I've now disabled password login via SSH and am forcing key based authentication.
Copying the key to my cell phone; I always have it with me, so I'll always have the means to connect to my router for SSH tunneling, whatever.
Also, I put a password on the key. It could be overkill, but it's not any less convenient to do so and adds a little more security to the whole process.
How so? At least on OpenWrt, SSH and Webif aren't even exposed to the wan side without manually changing the iptables rules first.
I guess it's the same on DD-Wrt.
The devices that were targetted appear to have some serious flaws, here's a cite from an analysis of the malware:
"Several revisions of the NB5 modem shipped with a flaw which meant that the web configuration interface was visible from the WAN side, accepting connections and allowing users to administer the modem using the default username and password of 'admin' from outside the LAN. Furthermore, some of these modems suffered from another flaw, meaning that by default, authentication was not enabled for the web interface - meaning no username or password was required."
It really boils down to the usual find-weak-logins style of attacks, only the target platform has changed.
This has put a new twist on the story of Rumpelstiltskin.
Don't set the password to a simple name you plan on say while talking to yourself and gloating.
shall we? OK! surveys show That that has lost about a project the project to OpenBSD wanker Theo a BSD over other survival prospects visit lizard - In other
The commercial routers don't have this option. Um like D-link, Linksys, etc. Unfortunately they are the majority of home/small enterprise routers But this would be the trick to use.
m0n0wall
maybe savvy users use bsd instead...
Things in a rear mirror might be behind you
I got DD-wrt and I am pretty everything is off by default when you first install.
I own a wrt54gl running ddwrt. I was initially worried, but double checked. I use a secure username and non-trivial password (not a word and number/letter combination), and also don't allow remote administration. Done.
My copy of Norton Anti-virus For Routers fails to pick up psyb0t even with the most current router definitions.
The helpdesk tech did say that if I was willing to add 4 gig of memory, that Vista for Routers is not affected by this bot.
That analysis is old.
And, it only targets DD-WRT/OpenWRT/Tomato routers configured in the way described in the article.
So the conclusion is "worm can infect machines with weak logins - now runs on mipsel too". :)
Thanks for the info.
The modem/router that Verizon provided for their DSL service had the firmware remotely upgraded. There is no way to avoid these updates. I hope it is secure. If someone roots that process, it will be the mother of all DDOS attacks.
A NYC lawyer blogs. http://www.chuangblog.com/
I'd imagine the password would be either "password" or "123456"
Can I feel smug that I use a dsl modem in bridge mode to a slack box (dual home) using iptables for NAT?
I am hoping...
Except it also attacks the http daemons on several models.
Mine's your mom's safe word.
We should have a -5 "Posted content in subject field" mod, of which everyone gets to use it once per day.
That would take care of that stupid habit right quick! ... of course it would need meta-moderation from hell to stop abuse.
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
WTH have you been doing playing with my luggage
"Stop" doesn't strike me as being a very secure password, even if you add a few exclamation marks.
What meta-moderation?
For a site about things like basic rights, Slashdot users sure do like to censor "dissent".
If this attack is combined with some PC-based worm, it will be much more effective. Routers that are vulnerable from the WAN side can be attacked by zombie PCs. The router can then be reprogrammed to try to attack anything that attaches on the WAN side, bypassing any firewalls in the router. The attack on the PC, of course, includes the code that attacks routers.
We need more devices that boot from a true read-only medium. Yes, upgrading is a pain, but most devices never get upgraded anyway. At least then they'd be stable.
Oh well. Looks like "open source" routers weren't such a hot idea after all.
It was fun while it lasted, but now they are looking like a liability.
OpenWRT is a linux based embedded operating system.
Surely this is a first. Sure nix boxes and devices get hacked all the time, but I assumed that such automated attacks were natively difficult on linux?
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
So do Linux based Open WRT modems...
The article title ought to have been "Botnet targets Linux-based routers. OpenWRT/DD-WRT are vulnerable"
(Salient quote/excerpt from the article featured here -> "any linux mipsel routing device that has the router administration interface or sshd or telnetd in a DMZ, which has weak username/passwords (including openwrt/dd-wrt devices)", after all...
APK
P.S.=> Yes, yes, weak passwords - &, yes, same thing can happen on other device quite possibly as well (however, the fact this router uses Linux must be extremely aggravating to have happen, & especially because it's /. & the crowd here can be very "Anti-Microsoft/Anti-Windows" much of the time? It doesn't make me wonder WHY the word "Linux based" was left out of the title here either, lol... so, I had to toss this little tidbit into the mix, just to see how it "stirs up the sauce" here is all, & after all, facts are facts)... Also?
DRS did you Linux people a favor, in a "left-handed" kind of way, but by this being discovered because of his arrogance & yes, honesty? It's now uncovered @ least and thus, can be fixed... apk
Yeah unless you generated them on a Debian machine...
all was belonged to y'all?
I have a WRT54G v3.0 router using the linksys v4.21.1 firmware.
I am using WPA2 Personal w/ 256-bit key[randomly generated], wireless MAC filter[whitelist] enabled, firewall enabled, block WAN request filter enabled, VPN passthrough[IPSEC,PPTP,L2TP] disabled, DMZ disabled, 256-bit randomly generated router password, and remote management and wireless access disabled.
So, am I [reasonably]safe from this thing?
Power does not corrupt - power attracts the corrupt.
While playing around with the fonera routers I already predicted issues like this: http://stefans.datenbruch.de/lafonera/whywedidit.shtml Consumer routers without decent firmware support are a even greater risk than unpatched windows systems; while access to the latter will probably be noticed, the profile of a hijacked routers stays low to its owner.
Life is just nature's way of keeping meat fresh.
There's lots of ways to exploit cheapo home routers, whether they're running custom firmware or stock stuff.
- Linksys firmwares have had shell execution vulnerabilities (that's how it was originally discovered that they were running Linux in the first place) as well as remote access vulnerabilities (where turning it off didn't actually work), among others.
- Many of the custom firmwares (DD-WRT in particular) are vulnerable to rather trivial XSS attacks. Yes, visit the wrong webpage with malicious javascript and your router can get owned.
- Not to mention the large number of routers with default passwords out there...
A mildly clever script could gain a large foothold quite fast, without even having to resort to password guessing.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
The problem is that these are slightly more savvy idiots. :)
Lenin would have called them Useful Idiots.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
People are over confident. We say we don't have to worry about a Linux based devices be cause Linux is secure, and so we configure it insecurely.
This is not just flamebait, but a serious policy: IRC has been a popular protocol for years, but with the advent of more secure and less abused protocols, there is no modern excuse for permitting IRC through any network or system firewalls. That helps cut the painful-to-monitor control channel.
In fact, most corporate and institutional firewalls should only allow a few registered and useful protocols through their breaches, such as HTTP, HTTPS, SMTP, and SSH, and even those can often be funneled to a small set of securable servers. Yes, it interferes with the random-service-of-the-moment that some folks demand as their right. If they want such rights, they can pay the cost of running a host isolated by more secure firewalls and software management, outside the more trusted internal environment: folks should not expect both easy sharing of resources, and external access.
It probably is (most cheap routers are) but it doesn't matter. Default firmwares for consumers routers don't have shells, let alone root ones.
This affects 3rd party firmwares.. DD-WRT and the like, that offer shell access. Further it requires that you open that access to the world (which isn't the default on any version I've seen).
I wear the AC hat with shame.
dont forget the -1 Off topic one! (sorry just had to!)
Deny hosts with some pretty lax settings should included on devices running embedded linux.
Comment removed based on user account deletion
Wouldn't it be substantially easier to just set a really strong SSH password and use key-based auth if you need to configure your router remotely?
You're interrupting the flow of this conversation.
You may need to down a few pints before posting in this topic. Or at least this particular thread.
Yahoo cached version of DroneBL announcement at http://dronebl.org/blog/8
http://74.6.239.67/search/cache?ei=UTF-8&p=http%3A%2F%2Fdronebl.org%2Fblog%2F8&fr=ubuntu&u=dronebl.org/blog/8&d=XjpWTp2uSg7q&icp=1&.intl=us
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finish a sentence in the comment.
having SSH disabled is not an option if you have a Vonage router! I'm just hoping that they have a strong password set! Has anyone figured out how to tell if your router has been compromised?