Drive-By Pharming In the Wild

An anonymous reader writes "Symantec reported Tuesday that the first case of drive-by pharming, in which a hacker changes the DNS settings on a customer's broadband router or wireless access point and directs the link to a fraudulent Web site, has been observed in the wild. The first drive-by pharming attack has been observed against a Mexican bank: 'It's associated with an e-mail pretending to be from a legitimate Spanish-language e-greeting card company, Gusanito.com,' says Symantec Security Response principal researcher Zulfikar Ramzan. Inside the e-mail is an HTML image tag but instead of displaying images, it sends a request to the home router to tamper with it."

Pfft

So, I suppose this "hack" fails entirely on any router which... well, either has a default password or (like any high end router) doesn't use HTTP basic authentication? No worries for me, my 3com is safe as houses.

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My AMD X2 'router' is also immune.

Having a real workhorse as your router improves security dramatically as well as allowing you to do some really cool things. :)

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If that's a dedicated router then its overkill.

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lol. Of course it would be overkill if that was all it did.
Its a home server with TV card, terrabyte raid array, etc...

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So your router contains stuff you don't ever want to lose? Not quite the best idea.

Also, the A in RAID stands for Array. RAID Array is like ATM Machine or PIN Number.

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Hmm, personally I prefer my routers not to have too many potential vulnerabilities, yours sounds like a nightmare from that perspective. What you are telling me is that a box on the edge of your network, a box that presumably is very open to abuse also ha

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I use a SonicWall TS5 wireless at home. It is also completely immune.

Once again, cheap consumer junk FTL!

Most Pooter owners too dumb to own one

If you have a home network, there are several ways to secure it. Every router that I have ever owned have several characteristics. Look for the 'reset' key, make sure it is there and not like Asante where you have to short terminals 3 and 8 on the serial port...showin my age there folks. Make sure it is a real router and not a windows appendage. Do NOT use a PCI modem that you cannot disconnect fast. Use an external modem on a SERIAL port. Do not use a combination cable modem/router. This is foisted on many users, and as a default feature sets up remote administration from the outside. That remote admin 'feature' is 'supposed to allow customer engineers to help......' you out of all your money. Don't surf as administrator if microsoftintheheady or as root if a linux penguin. Thats just askin to get hosed. Yeah, I'm a ramblin old fart, but all these things I have picked up from experience. Definitely change the default password, 'admin' or whatever on the router to something realllly strange and long. Write that password down and put it in your wallet, your wife's ring box, or whatever. Do not even try to memorize it as you will forget it when you need it. Don't use 'DHCP' that routers and network vendors want you to do. This means that all home networks are on 192.168.1.0 or some predictable net address that all hackers try first. Use a REAL network with a real address like 192.168.205.89 or something. This forces hackers to really fail many many times in guessing your network setup. With a real network, hand out your own addresses and make them random in the third and fourth hex digits so that hackers will have to guess out each and every terminal on your net. Now add MAC security to your router so that the hacker not only has to correctly guess from a crore of non standard addresses to address it, but only those with the right computer NIC can even be qualified to guess the password! Having a switch available to shut down suspects in a hurry helps too. I could go on, but if you have followed all this rambling, print it out and do it.

Re:Most Pooter owners too dumb to own one

Good advice.

But you forgot something: When a friend brings their PC/PSP/PS3/Wii/Xbox/iPhone/iPod over, and wants to use it with teh Intarwebs, go ahead and set it up and give them the passphrase and IP assignment, but make sure you destroy your friend before they leave.

You can't allow any chance of your uber-obscurity leaking outside, right? Eventually, you'll eliminate all of your friends, but that has the nice benefit of eliminating the potential leaks.

Naw, better to keep it simple. Don't run as root/admin. Set an unusual password (something other than your SO or child's name is adequate). Set a different, unusual, and lengthy, WAP passphrase. Use the strongest encryption you can with the devices on your network (AES, AES / TKIP, or just TKIP, in order of preference).

Done.

MAC filtering? Disabling DHCP? IP address range hide and seek?

Bullshit. All that does is make it harder for you and the people you trust to use the network. And if I, the creepy dude in the van across the street, get to a point where any of those stupid tricks will start to matter, they won't make any difference at all. If I'm clever enough to get past WAP, then I'm clever enough to clone a MAC address while sniffing past the rest of your security-through-obscurity features.

[And what's all that talk about serial ports? Are we still in 2008, or did we just jump back 10 years?]

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With a real network, hand out your own addresses and make them random in the third and fourth hex digits so that hackers will have to guess out each and every terminal on your net.

Sounds like someone doesn't understand how DHCP and subnetting work. You

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Not necessarily..
It is also possible to change settings on a router using UPnP using a malicious flash script...
See http://www.gnucitizen.org/blog/flash-upnp-attack-faq [gnucitizen.org] for details.
Most home routers have UPnP turned on, so you're not safe just because you

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It's freaking annoying though. It should start as a low delay and grow instead. That way they can prevent crapflooding *and* annoy less users...

Let me guess... L: "admin" P: "admin"

Was it a Linksys with default settings?
http://www.google.com/search?hl=en&q=default+router+passwords&btnG=Google+Search [google.com]

Re:Let me guess... L: "admin" P: "admin"

There are 3 major combinations of default username/password comnbinations that cover the vast majority of home routers. They are U:admin P:admin, U:admin P:password and U:admin P: (that's right.. NO password.) This is true of Linksys, Dlink, Netgear, etc. With a bit of searching, you can even find this out from their very own websites.

Captcha?

It sounds like a simple captcha image on the router's login page would thwart this.

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except that they could just spoof the captcha like they did with porn websites.
captcha page => spoof captcha page so user solves captcha for program => "hack" succeeds.

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Which reminds me, Netgear routers seem to redirect 192.168.0.1 to 'routerlogin.com' (owned by Netgear, but actually maps to your router normally). A somewhat dodgy design decision really as it serves to obfuscate what's happening when newbies log on to th

Re:Captcha?

Or maybe force users to change the password.

Which one makes more sense? :P

Biggest Mexican Bank?

2Wire DSL routers to point the user's Web browser to a fraudulent bank site that mimics the site of one of the largest Mexican banks.

There is not much space to guess here, it is either Banamex or Bancomer...

Re:Biggest Mexican Bank?

Well yes is Banamex. This attack was reported during late last year. This exploits a vulnerability in 2WIRE modems, as documented in US-CERT http://nvd.nist.gov/nvd.cfm?cvename=CVE-2007-4389 [nist.gov]
Trend Micro has a more recent report on a variation of this attack http://blog.trendmicro.com/targeted-attack-in-mexico-dns-poisoning-via-modems/ [trendmicro.com]
The UNAM-CERT, also has the "Gusanito" exploit documented (spanish only) at http://www.seguridad.unam.mx/doc/?ap=articulo&id=196 [seguridad.unam.mx]
The attack overrides the modem's password...

Definition?

What does "drive-by" have to do with this kind of hack? Oh sure we've all logged into neighbors wireless routers and snickered because they've left the default password. Somehow I think "drive-by" part was coined by a guy who thought of exploiting unsecured wireless routers and changing DNS settings. Am I the only one who doesn't think "drive-by" applies to this kind of attack?

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For that matter, neither does "hack". Though the pure meaning of "hack" will be debated infinitely, I doubt that anyone would define it was 'using a broadly published default setting to change a config setting on a piece of hardware'. Generally it involves

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I dunno about anyone else, but to me it conjures up images of 90s-era Hollywood hackers. Suave guy in the driver's seat of a red car, his short, befreckled and bespectacled companion laboriously typing on a laptop while muttering things about "This is UNIX

British Telecom Home Hub

Anyone else notice that BT are taking this seriously - log on to the router's home page and it tells you they have changed the default admin password (well it will when you enter the unit's serial number as the admin password.

Enough with the default passwords.

If Bioware can sell $30 software with unique CD-Keys printed on the inside of each jewel case, why can't Linksys sell $40 routers with unique admin passwords printed on each manual. Or better yet, make the default password the last 6 digits of the LAN side MAC address, that can't be terribly hard to manufacture.

Seriously, you could even honestly market them as "more secure."

Re:Enough with the default passwords.

Several reasons. First, it's easier to change what gets stamped into a cd than what gets set into the silicon. Second, the cd key isn't actually unique to the CD, it just conforms to an algorithm that determines whether or not the cd key fits the criteria for the software and then, when on the network, checks to make sure that the cd key was actually sold and that it's unique.

Re:Enough with the default passwords.

It's easier to change what gets stamped into a cd than what gets set into the silicon

Nope. I do embedded software, and write the test suite all those devices go through before being shipped to the customer. It's pretty standard to set custom stuff at that time, including the MAC ID for the unit. It would be just as easy to change the password at that time.

Your comment about the CD key, however, is right on.

Re:Enough with the default passwords.

It would be trivial to use the LAN MAC address as the default password.

It would also be trivial for someone to run "arp" while connected to your access point. I agree that they need to use a random default password, but the MAC address would not be sufficient.

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the software doesn't check for the unique key it just checks that the key fulfills some criteria that makes a random guess at a key unlikely to succeed. It's the reason CD key generators work.

Gamers are used to it...

Linksys would have to write in the cost of supporting all those users who have lost/misplaced the passwords or their technical support.

$1 too much

LAN side MAC address, that can't be terribly hard to manufacture.

My guess: it would cost $50K in R&D, $200K in equipment costs, $0.40 in parts and $0.60 in labor/time for each unit to make this happen.

A beancounter somewhere would see that $1 as "cost

Re:Enough with the default passwords.

Because software can pop up a box on your screen saying "go look for the sticker on the box and type the letters and numbers (and maybe the dashes or maybe not, your guess is as good as ours) you see there into this box here then click the button that says 'OK'".

Hardware says "blink"..."blink"..."blink"... and user calls customer support, adding $10 to the cost of every sale.

Last two routers I bought fixed this

They came with a big piece of yellow tape over the power terminal and the LAN cable ports, which said "STOP. Put the CD in first, and follow the instructions on the screen."

The instructions on the screen were, predictably, written so that you could unders

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How about simpler... the router will NOT function until you set a username and password. It routes no traffic and redirects all web requests to the "Hey stupid user, pick a username and password, no you cant use linksys, router, admin, or password."

that

Cold War Redux

Only this time it's between Mexican scammers and Nigerian ones. For years Nigerian scammers have exercised hegemony in the arena, but now Mexican scammers have upped the ante with this "pharming gap." This can only lead to a scams arms race with other nations as proxies and victims of the complex maneuvering of the two camps. As a helpless American I don't know how long I can stand being the play thing of two foreign powers duking it out for hegemony.

By the way I'm rooting for the Nigerians in this grand campaign, at least their scams provide a laugh once and awhile.

Gusanito??

Dude, gusanito means literally "little worm"; I personally would never open an email saying "hey, you got a postcard from a little worm!". I don't know who would...

Fankly, I'm suprised

...that this doesn't happen more often. I can drive through Seattle (and presumably any large city) with my laptop running a wireless network sniffer. After about 10 blocks, I could easily get into no less than 25 wireless routers. They are all configured with the default credentials. Of course, I don't. Sometimes, when it's a law firm, government agency, or some other organization with tons of [other peoples] personal information, I will even call them up and let them know about it, as a courtesy. They usually tell me to take a hike. Then I can show up at their door offering my services as a 'security consultant' (for $200/hr). 'Look here' I say. 'Look how I am easily changing the settings in your router.'. That's usually about the time they wet their $400 slacks and write me a check.

Re:Fankly, I'm suprised

I presume you're being funny. What you're doing there is just as likely to land you in the hoosegow as a suspected terrorist or something of that nature as it is to make you money. This is not a time in U.S. history where being a Good Samaritan is even remotely a good idea.

Re:Fankly, I'm suprised

...that this doesn't happen more often. I can drive through Seattle (and presumably any large city) with my laptop running a wireless network sniffer. After about 10 blocks, I could easily get into no less than 25 wireless routers. They are all configured with the default credentials. Of course, I don't. Sometimes, when it's a law firm, government agency, or some other organization with tons of [other peoples] personal information, I will even call them up and let them know about it, as a courtesy. They usually tell me to take a hike. Then I can show up at their door offering my services as a 'security consultant' (for $200/hr). 'Look here' I say. 'Look how I am easily changing the settings in your router.'. That's usually about the time they wet their $400 slacks and write me a check.
--

"It's a simple question, doctor.
Would you eat the moon if it was made of ribs, or not?"

CORRECTION: Would you eat the moon if it were made of ribs, or not?

In this case, the verb "to be" is in the subjunctive mood, which is used to indicate a situation that is hypothetical, conditional or somehow not certain.

Now, this correction is just a courtesy. However, if you tell me to take a hike, I will show up at your door with A Writer's Reference by Diana Hacker, and you can scratch me out a check. Sorry, I don't know how much you paid for your pants.

Re:Fankly, I'm suprised

You don't correct the grammar of a quote, douchebag.

You do if the quote [imdb.com] is quoted incorrectly with poor grammar, douchebag.

Idiots with default passwords get pwnd, news at 11

nothing to see here... move along, folks

I gotta wonder..

who manages to get a home router to work out of the box with no configuration? And if you're doing configuration to get your router to work, why are you not setting the password to something other than the default? Seriously, some people need a good kick

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Except many people don't actually mind sharing.

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We're not talking about the SSID or WPA or WEP here.. we're talking about the administration password on the router.

DNS cache poisoning

src [trusteer.com]

The paper shows that BIND 9 DNS queries are predictable i.e. that the source UDP port and DNS transaction ID can be effectively predicted. A predictability algorithm is described that, in optimal conditions, provides very few guesses for the "next" query (10 in the basic attack, and 1 in the advanced attack), thereby overcoming whatever protection offered by the transaction ID mechanism. This enables a much more effective DNS cache poisoning than the currently known attacks against BIND 9. The net effect is that pharming attacks are feasible against BIND 9 caching DNS servers, without the need to directly attack neither DNS servers nor clients (PCs). The results are applicable to all BIND 9 releases [1], when BIND (the named daemon) is in caching DNS server configuration.

Langfeldt's DNS how-to [tldp.org]

Pharming???

Will these terrible names, which apparently attempt to draw an analogy between a computer-related misdemeanor and some agricultural pastime, never end? I'm just waiting for some guy from F-Secure to call porn 'phucking'.

Worse possibilities

If you change the proxy settings on routers that have them, you could wreak all kinds of havoc, as you'd have access to all traffic, not just dns requests. Or, you could update the firmware to something custom, with all kinds of sneaky badness hidden with

Let me explain

I live in Mexico, and yes, the bank name is Banamex (owned by Citibank) and this is how the hack works:

The most prominent ISP in Mexico (Telmex) uses 2wire gateway modems, most of them wireless enabled. Security is turned on by default using serial numbers so no one from outside can login "easily".

However, there is no default security from the inside, so the gusanito.com postcard contains a malicious flash program that sends a special URL to the modem that adds a DNS entry to its local name resolution table pointing www.banamex.com to a pharming site.

Next time you open IE or any other browser and open www.banamex.com you'll get redirected to the other site.

This easily solved putting a user password on the modem configuration, but not all people care to do that.

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Sorry to say this but the attack overrides the modem's password, the attack from Gusanito and similar attacks (ie El Universal) probes with different common 2WIRE router addresses to get to the MDC. Fortunately it is not that elaborated... This attack was

Look for the "https:"

As I understand it, even with this so-called pharming technique, the bad guys still cannot correctly spoof an "https:" page... at least not without compromising the private key used to secure the SSL connection, or compromising the private key of the certificate signing authority.

When I explain to people how to use the Web, I always tell them to look for the security indicators [oreilly.com] before doing anything involving money.

P.S. I wouldn't be surprised if the bad guys here added Javascript code to their fake bank site, to rewrite the address bar of the web browser to show the "https:". This is why I prefer to do all my online banking with Javascript disabled; thank you, NoScript [noscript.net].

steveha