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D-Link Router Backdoor Vulnerability Allows Full Access To Settings
StealthHunter writes "It turned out that just by setting a browsers user-agent to 'xmlset_roodkcableoj28840ybtide' anyone can remotely bypass all authentication on D-Link routers. It seems that thttpd was modified by Alphanetworks who inserted the backdoor. Unfortunately, vulnerable routers can be easily identified by services like shodanHQ. At least these models may have vulnerable firmware: DIR-100, DI-524, DI-524UP, DI-604S, DI-604UP, DI-604+, TM-G5240."
Are these people too stupid to know that eventually, somebody _will_ analyze their firmware and find this? I think it is time to make them liable for a bit more than the device when things like these get found. Say, 10x the new value of the device to any customer that wants to give it back.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
That the consumer is always so proactive with updates that they'll upgrade their router the instant a fix is released.......NOT.
"A quick Google for the “xmlset_roodkcableoj28840ybtide” string turns up only a single Russian forum post from a few years ago, which notes that this is an “interesting line” inside the /bin/webs binary. I’d have to agree."
Even if they do, it sounds like they'll be almost four years late.
And the post points out (in 2010) that if you reverse the string it was "edit by 04882 Joel Backdoor" so it was clearly a backdoor.
The big scandal here is how can a backdoor be known since 2010 and not revealed??!!!
Read backwards it reads the same as the comment subject. Is this the guy behind it? http://www.joesdata.com/executive/Joel_Liu_421313008.html Assuming good will, it seems like debugging code left in the final firmware release.
I'm always amazed to read about things like this because most engineers are not morons. Why would they do it? How could they not know it would be discovered?
The Black Hats have probably known about this for a long time...
If you want news from today, you have to come back tomorrow.
PDF link, published earlier this year, shows how many manufacturers use a stack with a UPnP vuln that gives root, even from the WAN side:
http://www.defensecode.com/public/DefenseCode_Broadcom_Security_Advisory.pdf
Point is, you probably weren't as safe as you thought you were, even before this new disclosure.
I think a huge problem with consumer-grade wifi routers today is that as manufacturers race to support new models with new wifi standards and new competitive feature sets, older models quickly become abandonware. There's very little guarantee around firmware updates for critical vulnerabilities, and end users are mostly oblivious to being at risk. By the time you pick up that $80 model from the store it's probably borderline EOL already.
The Beatings Will Continue... Until the Firmware Improves.
How to bury your company's reputation with one password.
D-link's rep was buried long ago.
If you want news from today, you have to come back tomorrow.
Because friends don't let friends run crappy firmware with back doors/known problems.
http://www.linuxpromagazine.com/Issues/2010/119/Security-Lessons-Linux-WAP/(tagID)/337
D-link's rep was buried long ago.
I'd tend to say that D-link's rep is long-lived and very consistent.
Heay!
That's the combination on my luggage!
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
There is a systemic complete and total regard for basic tenets of security in nearly the entire home router/cpe market.
Start with crypto - no hwrng and a known "less than ideal" version of /dev/random to feed your "secure" wpa and ssh sessions.
Worse:
There is no privilege separation in most routers, which was ok when they were single function devices - BUT: not ok, when vulnerability via services like samba can be used to root most of the top 10 current home routers:
http://securityevaluators.com/content/case-studies/routers/soho_service_hacks.jsp
Once an attacker p0wns your home gateway they can change your dns to malicious sites, as dnschanger did:
http://www.dcwg.org/
or have it participate in botnets, or inflict further attacks on unsuspecting devices both inside and outside your firewall, or sniff your traffic - there is no security when your front door is left wide open.
What nearly every home router and cpe manufacturer is shipping is **rotware**, running 4-7 year old kernels with known CVEs, and 10 year old versions of critical services like dnsmasq. You'd think that new 802.11ac devices available for this christmas might have some modern software on it, but just to pick out a recent example - the "new" netgear nighthawk router runs Linux 2.6.36.4 and dnsmasq 2.15, according to their R7000 gpl code drop -
http://kb.netgear.com/app/answers/detail/a_id/2649
Brand new hardware - 4+ and 10 year old software respectively.
It's unfair of me to pick on Netgear, every router I've looked at this christmas season has some major issues.
Right now, the only current hope for decent security in home routers is in open, modern, and maintained firmware. And I wish the manufacturers (and ISPs, AND users, and governments) understood that, and there was (in particular) a sustainable model for continuous updates and upgrades as effective as android's in this market. I don't care if it came from taxation, isp fees, or built into the price of the device - would you willingly leave your networks' front door open if you understood the consequences?
Rotten routers with closed source code, and no maintenance, are a huge security risk, and they are holding back the ipv6 transition, (and nearly all current models have bufferbloat, besides)
How can the dysfunctional edge of the Internet be fixed?
This is NOT a small, obscure problem for users of DLINK routers. Although it does not open up Wifi access or anything like that, having access to the configuration panel of your router is bad news even from inside the network. I can't think of anyway to automatically exploit it via a browser (XSS-style) but a small executable (or trusted Java applet, for instance) could do it.
Additionally, I wonder how many small establishments are offering free wifi using DLINK equipment. Those networks are now vulnerable.
If I was a bad(er) guy, the first thing I would change would be the DNS settings. Forcing all computers behind the router to use a DNS I control opens up all sorts of interesting ways to mess with people.
sheep.horse - does not contain information on sheep or horses.
Well are you running an administration service on an open Internet facing port?
Your router won't get a chance to read the user agent string if you don't allowed an inward connection.
Then all you have to worry about is your insiders.
Sig Battery depleted. Reverting to safe mode.
Read it and weep:
http://www.washingtonpost.com/world/national-security/us-spy-agencies-mounted-231-offensive-cyber-operations-in-2011-documents-show/2013/08/30/d090a6ae-119e-11e3-b4cb-fd7ce041d814_story_1.html
"Much more often, an implant is coded entirely in software by an NSA group called Tailored Access Operations (TAO). As its name suggests, TAO builds attack tools that are custom-fitted to their targets. "
"Tailored Access Operations has software templates to break into common brands and models of “routers, switches and firewalls from multiple product vendor lines,” according to one document describing its work."
So on the one hand they're supposed to defend US networks from attack, while on the other hand they have detailed knowledge of these backdoors and use them for their own use while keeping them secret.
So yes, the NSA did have a hand in it, at the minimum it kept it secret while exploiting it.
In most of the companies that do such gear, the chap(s) in charge of actually developing and making them are treated as disposable cost factors. Who are under constant threat of being outsourced to some third world country. And the products they develop are basically abandoned once the next release hits the shelves, otherwise the incentives to buy new stuff would not be as high.
All the while the Cxx who "supervise" them (and who in a lot of cases couldn't even configure the products the company makes, let alone really care) walk away with more or less obscene bonuses. You know, just to show the little guys who is boss, and so.
Not a big surprise, then, that the developers apparently don't put their entire energy in making the best possible product. Would you, in their stead?
So it looks like this was a deliberate addition so that the router's internal tools could use http requests to change config. Why didn't they just check for incoming requests from localhost? Surely that would have been simple and safe enough? So instead they create something that they *know* is a backdoor.
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
D-Link should update their firmware: Joel left the company a long time ago. And you should never hard-code usernames in a firmware, only group names. This is basic stuff.
As a software engineer who has worked on some larger projects, I can tell you that you are in fantasy land if you think that every line of code can be vetted without spending a small fortune on code review. Those costs might be justifiable for a project like a space shuttle guidance system, where the cost of failure is billions of dollars and multiple lives, but nobody is going to shell out that kind of budget for a sub $100 consumer router.
HA! I just wasted some of your bandwidth with a frivolous sig!
Why do all these router vendors even bother producing their own nonstandard firmware?
Most of the hardware is based around a small set of common chipsets anyway, so why not use an existing firmware such as dd-wrt or openwrt.
http://spamdecoy.net - free throwaway anonymous email - avoid spam!
Remind me never to pick you as a team-mate for Trivial Pursuit.
How about this one from a month ago?
You can also compare Apple's 2095 vulnerabilities for 97 products to D-Link's 43 vulnerabilities for 40 products.
// MD_Update(&m,buf,j);
Minor nitpick - you're thoroughly mistaken. The National Council of Examiners for Engineering and Surveying has standards for certifying software engineers just like any other branch of engineering.
"The term engineer is reserved for disciplines requiring strict standards and provable output"
Perhaps you're unaware that software can be much more provable than concrete or steel. Dlink could have had strict standards that would have prevented this problem. Few developers employ engineering methods properly, and few developers create software that is known to be reliable.
Most people building software are not engineers, just as most people building houses are not engineers and most people building machines are not engineers. Go back to your Engineering 101 book and look up the definition of "engineering". It's 100% applicable to the design of software systems. People simply fail to apply it where they should, in many cases.
The fact that I can build a shed without an engineering degree doesn't mean civil engineering doesn't exist, and simple software doesn't mean there's no such thing as properly engineered software systems.