AT&T, 2Wire Ignoring Active Security Exploit [Updated]

An anonymous reader writes "2Wire manufactures DSL modems and routers for AT&T and other major carriers. Their devices suffer from a DNS redirection vulnerability that can be used as part of a variety of attacks, including phishing, identity theft, and denial of service. This exploit was publicly reported more than eight months ago and applies to nearly all 2Wire firmware revisions. The exploit itself is trivial to implement, requiring the attacker only to embed a specially crafted URL into a Web site or email. User interaction is not required, as the URL may be embedded as an image that loads automatically with the requested content. The 2Wire exploit bypasses any password set on the modem/router and is being actively exploited in the wild. AT&T has been deploying 2Wire DSL modems and router/gateways for years, so there exists a large vulnerable installed base. So far, AT&T/2Wire haven't done anything about this exploit." Update: 04/09 17:48 GMT by KD : AT&T spokesman Seth Bloom sends word that AT&T has not been ignoring the problem. According to Bloom: "The majority of our customers did not have gateways affected by this vulnerability. For those that did, as soon as we became aware of the issue, we expeditiously implemented a permanent solution to close the vulnerability. In fact, we've already updated the majority of affected 2Wire gateways, and we're nearing completion of the process. We've received no reports of any significant threats targeting our customers."

Anybody have any ideas...

on how to walk my mom through changing her IP scheme and modify the hosts file? Do I have to go over there?

Re:

Nah, I already got that for her.

Re:Anybody have any ideas...

...how to walk my mom through changing her IP scheme and modify the hosts file? Do I have to go over there?

Oh, come on. Don't be so lazy. It won't kill you to walk up the stairs and across the living room.

Re:

Most of them have wireless, provided he's getting good coverage in the basement he could do it from there.

Funny Post

Me Chinese
Exploit SOCKS,
Me put malware
On your box!

Re:Funny Post

That would be slightly funnier if the exploit actually involved SOCKS. In reality, it looks like a simple CSRF [wikipedia.org] attack. (Is it just me, or are we seeing a lot more of those lately?)

Exploit doesn't seem to work on my 2700HG-B

I tried their example for adding example.com to DNS (here as not a live link; copy it paste it yourself at your own risk):

http://192.168.1.254/xslt?PAGE=J38_SET&THISPAGE=J38&NEXTPAGE=J38_SET&NAME=www.example.com&ADDR=127.0.0.1

and all it did was leave me at the "enter system password" page. Yes, my router has a non-default system password. The system software release is 4.25.19.

Re:Exploit doesn't seem to work on my 2700HG-B

This exploit is CSRF (Cross-site request forgery). This means that you have to have an active authenticated session to your router in your browser. When you click the link and your browser is already authenticated, it will send your session cookie along with the HTTP request, and the web server in your router will know you are already authenticated, and execute the command you gave it.

Try logging in to your router, open a new tab, and click on that link again and see if it works.

Re:

I'm sure that if I was already logged into my router, that link would work, because I know the 2wire uses cookie based authentication.

But why on earth would I be logged into it??? Its status pages do not require a login, so the only reason to log in wo

If you have a website, paste the following code

Thanks so much for that URL.

If you want to join into the phun, put the following onto your website (or onto somebody else's website, if he happens to still use IIS):

<img src="http://192.168.1.254/xslt?PAGE=H04_POST&amp;PASSWORD=admin&amp;PASS

I'm not suprised, given my experience with 2wire

One of the worst routers I have ever had. Besides resetting itself arbitrarily, it would forget it's own settings and revert to the default, or half of the settings would revert to the default and the other half.... ? Also, right before I threw it out my window, it forgot it was a wireless router completely. I mean, it reset itself one last time and quit broadcasting completely. Even the setup pages lost the wireless part. I could manually enter in the wireless setup URL, and it would show one with random values in each field.

I'm just waiting for a nice cooler day to take it to the shooting range. The manual traps and some shotgun pellets might make up for all my anguish.

Bridge Mode

Never trust these combination modem/router/firewalls. Put the thing in bridge mode and run a real router behind it (such as an old pc running Debian or OpenBSD or even an old Cisco).

Re:

Perhaps if we're worried about security issues, administrating a local copy of BIND isn't the greatest plan [nist.gov].

from the DSL reports forums

You can implement a temporary fix yourself. The first post in the following thread describes how to protect yourself until 2wire fixes the issue 2Wire Cross Site Request Forgery Vulnerability .

Here is a short summary:

First, change the IP scheme that the 2wire is using for your home network. Specifically, change the IP address of the 2wire router itself. This will prevent attacks against 192.168.1.254.

Next you have to prevent attacks against the domains "home" and "gateway.2wire.net". You can do this a couple of ways. You can modify your hosts file and point those domains to 127.0.0.1... or you can hardcode the dns settings into your computer so that your computer is not using the 2wire to resolve domain names.

Of course the bottom line is 2wire needs to plug this hole. When will that happen? Who knows.

2Wire routers also very weak on WEP

2Wire access points also come hard-coded for 56-bit WEP, which can be cracked in seconds. I have a list of hundreds of WEP keys I got just from riding my bicycle around San Francisco with a laptop chugging away in my backpack. These are by far the worst access points ever deployed, and they are, sadly, also the most widely deployed in the USA.

Re:

hmm. the 2wire boxes i see (2700s) are default WEP, but have the option for WPA and WPA2.

Re:2Wire routers also very weak on WEP

Well, the 2Wire is the box the telco sends you when you order an ADSL line, so your average ignorant consumerbot has no reason to get anything else.

Re:Sasktel customers

From TFA [securityfocus.com]:

Vulnerable:
2Wire 2071 Gateway 5.29.51
2Wire 2071 Gateway 3.17.5
2Wire 2071 Gateway 3.7.1
2Wire 1800HW 5.29.51
2Wire 1800HW 3.17.5
2Wire 1800HW 3.7.1
2Wire 1701HG 5.29.51
2Wire 1701HG 3.17.5
2Wire 1701HG 3.7.1

Re:Sasktel customers

yeah, but DSLreports is reporting [dslreports.com] that the 2700s and 2701s are vulnerable, so i'm not sure which is correct

Re:

I still have my old Speedstream 5100b. :)

I'm not sure I get the joke, but if it's funny, it might be even funnier that, IIRC, I have a model with a lower number. With the exception that it doesn't reset/resync after a power failure, I guess it works likes

Re:I'm just glad...

Because 300 BPS modems were TOTALLY invulnerable to attacks...

+++ATH0

Re:

tell him to enjoy the blankets I sent

Re:of course they won't care?!

We don't care. We don't have to. We're the Phone Company.

Re:

Easy, if they think it's no skin off their back for not updating their hardware, they think they can save money by not doing it. If they have 10,000 customers and it's $100 to replace one of their old modems, then it's a million bucks to swap them all out

Re:Large install base

By default they come with 32 bit WEP

You're closer to the truth than you know. They use 64 bit (i.e. 8 byte) WEP by default, which is really 40 bit (i.e. 5 byte) WEP since three of those bytes are the IV and broadcast in the clear. However, 2WIRE has an awful policy of printing the WEP key on the side of the modem in hex format and not using the digits A through F.

So the default key, written in hex, is a "decimal" number somewhere between 0,000,000,000 and 9,999,999,999. That's only 10 billion possibilities, or about 33.2 bits of entropy. Your computer can crack through that in a day or two with only three or four captured packets.

When I discovered this (and, of course, got stonewalled by 2WIRE), I wrote a patch for aircrack (now aircrack-ng) that programs it to search only the binary coded decimal keyspace. I named this option -t in honor of "Two Wire" for their terrible security.