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Security Wireless Networking Hardware

Critical Flaw Discovered In DD-WRT 225

MagicM writes "A critical flaw has been discovered in DD-WRT, a Linux based alternative open source firmware for WLAN routers such as the fan-favorite Linksys WRT54GL. The flaw can give an attacker instant root access to the router merely by embedding an image with a specially crafted URL in a Web page (CSRF attack)." The linked page notes that a fix is being rolled out (build 12533) and gives firewall rules to thwart the attack if the fix is not available yet for a particular device.
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Critical Flaw Discovered In DD-WRT

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  • Yes, there's a fix for this, but what is the likelihood of every person who owns a Wifi router fixing this flaw?

    We talk about the dangers of homogeny, but this is exactly the type of thing that homogeny causes. All the routers with DD-WRT implemented to save costs, but in the end everyone is screwed.

    Just because we love Linux doesn't mean that we should sacrifice the entire ecosystem to that love. We need to nurture other implementations to prevent this type of virus from wiping out our entire networking in

    • Mod Parent Up (Score:3, Interesting)

      by zarthrag ( 650912 )
      You know, as much as I used to complain about the many different distros - you've got a damn good point.
      • Re: (Score:3, Insightful)

        by TheLink ( 130905 )
        Uh, they don't have to use different distros.

        If people just disabled remote admin (which you should do anyway) and used different router IPs (e.g. not 192.168.1.1 or the usual), then attackers either need to do additional stuff to figure out what your default gateway is (and thus presumably your router IP), or they need to have significant control of a PC attached to the internal network (and presumably able to access the router webpage).
        • Re: (Score:2, Insightful)

          by SCPRedMage ( 838040 )
          DD-WRT leaves remote admin off by default, meaning that this vulnerability only affects those few people who thought they had some need for remote admin access.

          I'll also agree that people should change the subnet that their network uses, but if they already have "significant control" of a PC on the network, then what's the point in going after the router?
        • Re: (Score:3, Informative)

          by Sleepy ( 4551 )

          >If people just disabled remote admin (which you should do anyway)

          FYI, the exploit is Internet-ready even if you turn off remote management.

          It's in the article, if you read it. Webpages (or flash, etc) can just craft a request to exploit this and in the process, turn remote shell ON.

          Web-managed routers will always be LESS secure than router types managed via local telnet or ssh. Such designs are immune to browser and cross site attacks... but they're more difficult to manage for novice users, which is w

    • by qoncept ( 599709 ) on Friday July 24, 2009 @09:12AM (#28806583) Homepage
      What are you talking about?

      1. If people not only updated the firmware on their router, but had to do hacks to get it on there, don't you think they're probably at least a tad more likely to keep the firmware up to date than Joe Blammo with the factory firmware installed?

      2. Do you think DD-WRT was really all that much more susceptible to having a flaw than, say, something from Cisco? Or, by the same thought process, do you think open source Linux is inherently more vulnerable than Windows?

      3. Homogeny? Huh?! Do you mean the homogeny that's defined has "a significant portion of huge nerds (though certainly not even close to a majority) uses this software" ? How many routers are being used in homes and small businesses around the world? You think enough of them are running DD-WRT to call it a homogeny? Name a router that you think has more instances of DD-WRT installed than the factory firmware.

      Software bugs happen. You don't need to get all philosophical about it. And besides, this is no more dangerous than the much larger number of people probably still using the default password on their router, and probably only slightly more dangerous than the huge number of people who don't have any kind of security. Relax.
      • by Anonymous Coward on Friday July 24, 2009 @09:27AM (#28806765)

        3. Homogeny? Huh?! Do you mean the homogeny that's defined has "a significant portion of huge nerds (though certainly not even close to a majority) uses this software" ? How many routers are being used in homes and small businesses around the world? You think enough of them are running DD-WRT to call it a homogeny? Name a router that you think has more instances of DD-WRT installed than the factory firmware.

        WRT54GL

        http://www.linksysbycisco.com/US/en/products/WRT54GL

        • I'd mod you up if I had points atm :)
        • by narfspoon ( 1376395 ) on Friday July 24, 2009 @09:38AM (#28806901)
          [Citation Needed]

          If you read the comments on NewEgg.com for that router model, not everyone mentions DD-WRT. Some use other 3rd party firmwares like Tomato or Open-WRT or custom builds. And believe it or not, some even write a positive review for the default factory firmware. The nice thing about that model ("L" version) is the extra memory headroom. Earlier models were stripped and crippled to run a really crappy default firmware from Linksys. BitTorrent crashes these small memory models often.

          http://en.wikipedia.org/wiki/Linksys_WRT54G_series#Hardware_and_revisions [wikipedia.org]
          • by cenc ( 1310167 )

            I would say likly the bufflow routers, as they get bad reviews for their factory firmware but great reviews for their hardware.

            By the way I run Tomato on both types.

        • Re: (Score:2, Funny)

          by troll8901 ( 1397145 )

          The router appears to glow in the picture.

          Does that mean the router has biochemical reactions involving free radicals as well?

          Someone call Greenpeace! There's a lack of environmental progress from router makers!

      • by HockeyPuck ( 141947 ) on Friday July 24, 2009 @09:37AM (#28806889)

        1. If people not only updated the firmware on their router, but had to do hacks to get it on there, don't you think they're probably at least a tad more likely to keep the firmware up to date than Joe Blammo with the factory firmware installed?

        You're assuming that all these people that installed dd-wrt on their router installed it on their own routers only. Not their parents, friends etc, and forgot about it.

        Do most open source projects have a mailing list in which ONLY important notifications like this go out? In comparison, two years ago I bought a coffee pot from Amazon, and the manufacturer issued a recall for the pot itself. Amazon notified me via email that there was a recall for the pot and provided instructions on how to get a new replacement glass pot. Trolling forums or slashdot isn't exactly my idea of customer service.

        If I had bought a Cisco/linksys router and there was a similar problem would I have been notified after registering the product?

      • Name a router that you think has more instances of DD-WRT installed than the factory firmware.

        Linksys WRT54GL. The one they market through online dealers (no brick-and-mortar stores that I know of) specifically for people who want a Linux-based router that's friendly to third-party firmware.

        rj

        • Bought mine at Fry's Electronics here in Atlanta so there is at least one B&M you can pick it up at. Only criticism I can really throw at it is the lack of draft n.

          I'm also running dd-wrt so I think I'll be updating it now.

      • I almost never update the DD-WRT firmware on mine.

        According to TFA the problem is with remote web gui control though, and thats pretty trivial to turn off (and since its off by default, I don't even have to do it).

      • 1. If people not only updated the firmware on their router, but had to do hacks to get it on there, don't you think they're probably at least a tad more likely to keep the firmware up to date than Joe Blammo with the factory firmware installed?

        I tend to not update DD-WRT on my routers all that frequently, because they just work. I do occasionally check for new versions and update as appropriate (as with most of my other apps, drivers, etc. as well). But when you're not constantly having problems with something, it's a lot easier to forget it's even there. You tend to check for Linksys firmware updates when your router locks up every few days, but months of uptime generally don't make you run out and try to find something new.

      • Re: (Score:3, Informative)

        by Khyber ( 864651 )

        "You think enough of them are running DD-WRT to call it a homogeny? Name a router that you think has more instances of DD-WRT installed than the factory firmware. "

        Buffalo WHR-HP-G54DD comes with it installed by default.

    • Re: (Score:3, Insightful)

      by nitsew ( 991812 )

      Yes, there's a fix for this, but what is the likelihood of every person who owns a Wifi router fixing this flaw?

      We talk about the dangers of homogeny, but this is exactly the type of thing that homogeny causes. All the routers with DD-WRT implemented to save costs, but in the end everyone is screwed.

      Just because we love Linux doesn't mean that we should sacrifice the entire ecosystem to that love. We need to nurture other implementations to prevent this type of virus from wiping out our entire networking infrastructure.

      What is the likelihood of any flaw on any system getting patched? I don't see how a vulnerability in DD-WRT is any different than if Cisco announced a major vulnerability in one of their systems. I bet just about the same percentage would be patched.

      • by Shads ( 4567 )

        In reality I would wager less of the dd-wrt routers would get patched, but only because a lot of them were deployed by non-professionals who will likely not see the news.

    • by middlemen ( 765373 ) on Friday July 24, 2009 @09:15AM (#28806625)

      We talk about the dangers of homogeny, but this is exactly the type of thing that homogeny causes. All the routers with DD-WRT implemented to save costs, but in the end everyone is screwed.

      As opposed to using the base software from Linksys/Cisco where you don't know where the flaws lie, and if someone figures it out, it rarely ever gets published on the web openly or gets fixed soon enough in a firmware update. How is that different ? At least if you use Linux, you have people who care, and only people who care about their networks or improved experience with their routers use DD-WRT/OpenWRT/Other in the first place. Most just use the default software on their routers, which remains unpatched for a large portion of its use if at all.

    • by Mad Merlin ( 837387 ) on Friday July 24, 2009 @09:19AM (#28806671) Homepage

      It's hardly an issue with every wireless router. For example, the Tomato firmware is not vulnerable to this. Furthermore, most routers with DD-WRT are custom flashed, they don't come stock with it.

      • Re: (Score:2, Informative)

        by Anonymous Coward

        +1 for Tomato, that firmware is awesome and rock solid.

        • Re: (Score:2, Interesting)

          by eredin ( 1255034 )
          I couldn't agree more. After a long history of sketchy routers that I had to reboot every other day, I bought the WRT54GL just so I could put third-party firmware on it. The rave reviews led me to Tomato. Simple to set up, great interface, lots of cool stats and graphs, and -- most importantly -- my up time is now determined by power outages.
          • by Khyber ( 864651 )

            Will the semi-crippled WRT-54GL that I have finally quit bugging out every time I use bittorrent if I used Tomato instead of DD-WRT, and does Tomato come with wireless bridging/repeater functionality?

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      If you had a PIX, Sonicwall, Monowall, Linksys, Netgear etc.. router and it had a similar flaw, you would be equally screwed because you still have to fix it. I hope you don't think using those products is 100% risk free and that they never need patched/updated.
      It doesn't matter if 1000 people are using [Router_X] or 100 million people are using it. This type of flaw on your equipment is not safer, better, worse, or any less of a flaw or risk to you and your network regardless of the overall penetration o

    • Re: (Score:3, Insightful)

      by Shads ( 4567 )

      What you're advocating, in a round about way, is security through obscurity.

      Security through obscurity doesn't work.

      All security through obscurity does is propagate a false sense of security that you're safe because you've not heard any major news headlines telling you that you're vulnerable... meanwhile, you've been rooted for 3 months.

      • by TheLink ( 130905 ) on Friday July 24, 2009 @10:18AM (#28807475) Journal
        I disagree. Security through obscurity works.

        For example: in this case if you had already changed your router's IP address, it would be harder for the attackers to figure it out. For example if you use the 10.35.79.184, the same url that can exploit thousands of other dd-wrt routers (e.g. http://192.168.1.1/etcetc ), won't work on your router. So there has to be an attack specifically targeting you[1]. Which rarely happens unless you're famous or have made yourself infamous (or well-hated amongst hacker circles).

        So you have more time to update your router or even have time to wait to see if the updates don't break other stuff first.

        You're not as vulnerable to zero-day attacks as other people.

        Same goes for putting running sshd servers on a different port. I could use port knocking or other other stuff, but so far running it on a different port works well enough for me.

        I actually have my sshd server bound on an IP and port that's unreachable from outside, and my firewall has a rule to forward outside connections to it. This way if a mistake happens and my firewall rules get disabled/cleared, ssh and other crap from outside won't work.

        [1] If a top hacker was targeting you specifically, they'd probably be able to pwn you.

        For example:
        1) I'm sure there are many zero-day browser/plugin exploits left (just look at how fast the pwn2own winners pwn stuff - they just sacrifice one of the zero-day exploits they have).
        2) I doubt most ISPs have locked their BGP stuff down, so the attackers could use "BGP eavesdropping/prefix attacks" to hijack your connections.

        With 1) and 2) you'd be merrily browsing your usual sites and pwned without noticing a thing- the hacker would just pass most of the traffic on, and just alter one or two connections to exploit the relevant browser bug.
        • As an additional layer in your security regimen, you bet. As security by itself, no way...which seems to be pretty much what you are saying, only you just didn't say it directly. As you said...:

          For example: in this case if you had already changed your router's IP address, it would be harder for the attackers to figure it out. For example if you use the 10.35.79.184, the same url that can exploit thousands of other dd-wrt routers (e.g. http://192.168.1.1/etcetc [192.168.1.1] ), won't work on your router...So you have more time to update your router or even have time to wait to see if the updates don't break other stuff first.

          However,...:

          Same goes for putting running sshd servers on a different port...but so far running it on a different port works well enough for me.

          Of course, all it would take for someone to discover that you were running sshd on an alternate port for them to run "nmap -sV -p1-65535" on your IP address. However, that is time consuming, and most hackers are after the low hanging fruit, so instead, they "nmap -sV -p22 1.2.3.0/24

      • by Khyber ( 864651 )

        Security through obscurity DOES work. I invite you to try exploiting any MenuetOS box. Good luck without knowing the actual hardware of the system and having the source code to the ASM-coded drivers written for each individual piece of hardware!

    • It's "homogeneity" (Score:2, Informative)

      by Merdalors ( 677723 )
      We have to nip this in the bud: it's "homogeneity" (Webster, Oxford)

      Sorry about that.

      • by BadAnalogyGuy ( 945258 ) <BadAnalogyGuy@gmail.com> on Friday July 24, 2009 @09:46AM (#28807001)

        langs morf. get use 2 it.

        • by AP31R0N ( 723649 )

          Should be modded insightful.

          Gods damned descriptivists.

        • by egburr ( 141740 )

          No. Languages may morph, but that is not a good excuse for looking like a lazy idiot. Typing text messages on a cell phone is a pain, but when you have a full keyboard there is no excuse for such lazy spelling.

          I have noticed, however, that all the phonics being taught in school are really making a mess of my kids' spelling abilities. They learn one way to spell a sound, and then all words with that sound must be spelled that way. Maybe it's a good thing to get all those annoying silent letters to disappear

  • Standard Practices (Score:4, Insightful)

    by karnal ( 22275 ) on Friday July 24, 2009 @09:05AM (#28806499)

    I was wondering: How can this attack be carried out if the external web management is turned off? From the article:

    Note: The exploit can only be used directly from outside your network over the internet if you have enabled remote Web GUI management in the Administration tab. As immediate action please disable the remote Web GUI management. But that limitation could be easily overridden by a Cross-Site Request Forgery (CSFR) where a malicious website could inject the exploit from inside the browser.

    The Shashdot blurb does state "The linked page notes that a fix is being rolled out (build 12533) and gives firewall rules to thwart the attack if the fix is not available yet for a particular device." but that statement doesn't curb a lot of the "The Sky is FALLING!" reactions....

    Basically, I would NEVER allow remote web management of a device if it's on the internet. I believe the default for DD-WRT is to disable it as well, so you'd have to go in and tell the device that you want to enable this feature. All in all, I think for most users, this issue is a non-issue.

    • by BigHungryJoe ( 737554 ) on Friday July 24, 2009 @09:08AM (#28806553) Homepage

      Maybe I'm misunderstanding, but if the exploit is "injected from inside the browser" then won't the management of the device be coming from the local interface, not the internet side?

      • Re: (Score:3, Informative)

        Yea, thats what I got from that statement too.

        The easy way is to go directly in through the remote Web GUI.

        slightly harder to go in through the browser running inside the network.
      • Re: (Score:3, Interesting)

        by Culture20 ( 968837 )
        Thus why you don't allow web management even on the local interfaces except with a specific IP that isn't your workstation. The possibilty of http redirects to default local IPs that routers use (attempting default password logins) has been around since their inception.
      • Yes, but you're hardly likely to try to exploit your own device, are you? Attempts to exploit the flaw will be coming from the internet. By turning off remote configuration, a malicious hacker would have to find a proxy server on your LAN and bounce the attack off that to your device.
        • Re: (Score:3, Interesting)

          coming from the internet, but executed from YOUR browser. That's the danger they're talking about.

          • by tolan-b ( 230077 )

            Indeed. Though CSRF flaws are also dependent on you being logged into the vulnerable application at the time that you visit the compromised website (or that the application doesn't require any login but I'd be very surprised if that were the case here).

    • Re: (Score:2, Redundant)

      by karnal ( 22275 )

      Alright, I'm a n00b. I didn't read that second line fully before posting regarding the injection.

    • by gamefreak1450 ( 887066 ) on Friday July 24, 2009 @09:14AM (#28806603)

      Basically, I would NEVER allow remote web management of a device if it's on the internet.

      Good idea, but this is a critical exploit because hackers can make an img tag load the malformed URL. If they can trick you into viewing that image, then your router will be compromised from your computer on the network. Disabling the external management will prevent internet users from compromising your router, but it is still vulnerable to local threats, as executed through the CSRF method.

      • Re: (Score:2, Funny)

        by Anonymous Coward

        Good idea, but this is a critical exploit because hackers can make an img tag load the malformed URL.

        What about dentists? Can dentists make an img tag to load the malformed URL too, or just hackers?

      • I'm guessing you could add it to an href in a stylesheet reference, a script src, or even as a link target. I don't see why this would be limited to just images.
    • by Minwee ( 522556 )

      I was wondering: How can this attack be carried out if the external web management is turned off?

      <A HREF="http://192.168.0.1/webmanagementinterface/ownyourfrakkingrouter.pl">Hey, since you're inside your network and able to access the web interface directly, why don't you click on this for me?</a>

      That's how. For bonus points load the exploit as an image and inline it on as many web pages as you can find.

      Need anything else explained? The London police probably won't arrest be for telling you

  • Worse than that (Score:4, Informative)

    by tomtomtom ( 580791 ) on Friday July 24, 2009 @09:05AM (#28806501)

    It's worse than a specially crafted image - there's a code injection flaw in the httpd server so merely accessing a URL that looks like "http://routerIP/cgi-bin/;command_to_execute" will do the trick. That URL can be put in a malicious tag on an HTML page and the user most likely won't even notice it.

    See the Register article [theregister.co.uk] on it from a couple of days ago.

    • by Lumpy ( 12016 )

      disable http.

      only use https for router config access.

      All of a sudden the attack vector is useless.

      • Congrats on not understanding how the internet works.

      • Re: (Score:2, Informative)

        by hoosbane ( 643500 )
        Um... no. The URLs that break this work just as well over HTTPS. And the firewall rule they offer to protect against the hack won't protect the HTTPS port, so you're actually *more* vulnerable over HTTPS. Of course, the CSFR attack can be mitigated by just not using the default IP range for your router.
      • Re: (Score:3, Interesting)

        by twistah ( 194990 )

        Did you bother even reading the article? The code is in httpd.c, which obviously handled both types of connections. I almost hate SSL sometimes because people equate it with security -- but not encryption or integrity, but that somehow it's a magical fix-all for whatever the security flaw is. I see this kind of thinking in IT people in charge of the enterprise and it scares me. Security is not about having a setting enabled, and it certainly requires much more analysis than a simple dismissive suggestion.

        • by egburr ( 141740 )

          I almost hate SSL sometimes because people equate it with security -- but not encryption or integrity

          Yeah, SSL really bugs me. Most of the time, I don't care about authenticating the server I'm connecting to. Most of the time, all I want is encryption between me and the server I'm talking with. In fact, unless I actually examine the certificate the server presented, my browser authenticating the server just tells me that the server has a certificate from a certificate authority my browser knows about. And

      • by tepples ( 727027 )

        only use https for router config access.

        Most home router owners can't afford $$$ per year for an SSL certificate for their routers. Or what am I fundamentally misunderstanding?

        Besides, let me fix the post to which you replied: It's worse than a specially crafted image - there's a code injection flaw in the httpd server so merely accessing a URL that looks like "https://routerIP/cgi-bin/;command_to_execute" will do the trick. That URL can be put in a malicious tag on an HTML page and the user most likely won't even notice it.

        • by 0123456 ( 636235 )

          Most home router owners can't afford $$$ per year for an SSL certificate for their routers.

          Which is good. Because if anyone ever feeds you a malicious https:/// [https] URL trying to hack your router, you'll get a bunch of dialog boxes coming up telling you that the certificate can't be validated... and you'll know something bad is going on.

          Basically, though, this is merely demonstrating again that web-based hardware admin is a really, really, really bad idea. It's an even worse flaw than my router which has a bug that allows any remote site to reconfigure DNS without a password by sending you a maliciou

          • by tepples ( 727027 )

            [Lack of a certificate for SSL to a home router] is good. Because if anyone ever feeds you a malicious https:/// [https] [https] URL trying to hack your router, you'll get a bunch of dialog boxes coming up telling you that the certificate can't be validated... and you'll know something bad is going on.

            Then how do you get past the dialog boxes when you are trying to legitimately manage your router?

            Basically, though, this is merely demonstrating again that web-based hardware admin is a really, really, really bad idea.

            What protocol for administration of a home-office network appliance would you recommend, if not HTTP or HTTPS?

        • I agree that HTTPS will not solve this problem. But if you're paying $$$ you're paying too much. You can get 99+% of web users with certificates that cost $30/year or less.

          Moreover, if it's your own browser and your own computers, you can simply set up your own CA, add the CA cert to your local X.509 authority lists, and then issue a many certs as you'd like for $0. There's a small time investment if you don't already have OpenSSL setup and configured somewhere, but probably not even $30 worth if you know w

    • Comment removed based on user account deletion
    • It's worse than a specially crafted image - there's a code injection flaw in the httpd server so merely accessing a URL that looks like "http://routerIP/cgi-bin/;command_to_execute" will do the trick.

      I tried to go to that URL but I just got a message "command 'command_to_execute' not found". Why doesn't it work?

      • by twistah ( 194990 )

        I am guessing this was meant as a troll/joke, but, you may to actually put a real command in there.

  • by Anonymous Coward on Friday July 24, 2009 @09:26AM (#28806751)

    DD-WRT just isn't compliant with the GPL on so many levels.calling it an "open source" firmware is a lie and a disgrace to the open source community.

    The open source parts are OpenWRT.

  • by janwedekind ( 778872 ) on Friday July 24, 2009 @09:28AM (#28806771) Homepage

    ... to add a firewall-rule fixing this issue.

  • How did this happen? (Score:5, Interesting)

    by MobyDisk ( 75490 ) on Friday July 24, 2009 @09:48AM (#28807023) Homepage

    The bug resides in DD-WRT's hyper text transfer protocol daemon, which runs as root.

    Whhaaat??? And the command looks like:

    http://routerIP/cgi-bin/;command_to_execute

    Whhaaat???

    This is a bug even Adobe would be ashamed to admit. An http server, running as root, accepts arbitrary commands, without authentication, embedded in a URL? That's not a bug thats... that's a design flaw... no... that's... unbelievable!

    Is there a legitimate reason that the http daemon runs as root? (It is for embedded devices...) Or that commands are accepted over HTTP GET like that?

    • by Minwee ( 522556 )

      An http server, running as root, accepts arbitrary commands, without authentication, embedded in a URL? That's not a bug thats... that's a design flaw... no... that's... unbelievable!

      Actually, that's how the new firmware got on the router in the first place.

      Seriously, look it up.

    • by nmos ( 25822 )

      This is a bug even Adobe would be ashamed to admit.

      Some of the DSL modems around here (I think it's the 2-Wire brand) had a similar bug. Basically if you know the exact url of one of the modem's built in commands you can bypass the admin password.

    • by Eil ( 82413 ) on Friday July 24, 2009 @05:31PM (#28813935) Homepage Journal

      It's one of the reasons I don't use DD-WRT. For an Internet-facing security device, the author seems to have little regard for security.

      Also, the firmware isn't really open source and the author is a humongous hypocrite.

      Use Tomato [polarcloud.com] or OpenWRT [openwrt.org].

  • NoScript! (Score:3, Informative)

    by WD ( 96061 ) on Friday July 24, 2009 @09:52AM (#28807099)

    NoScript actually mitigates this vulnerability. The ABE feature, in particular:
    http://noscript.net/abe/ [noscript.net]

    So although I added the firewall mitigation in dd-wrt, I was pleased to find that NoScript blocked the CSRF request before it even got to the router.

    • Re: (Score:3, Informative)

      by Vectronic ( 1221470 )

      That might help some, but what about:
      1. Places that have 40 computers, running 3 different browsers.
      2. Your friend/relative that comes over with their laptop
      3. Embedded browsers in applications (even if they use your FF/Gecko does it load NoScript for those?)
      4. That time you disabled NoScript cause something was "all fucked up", and you may as well "test"
      5. What if someone got to the NoScript update servers?
      6. ???
      7. Loss of profit!

  • An easy work around for this is make the router URL IP address on the LAN side not easily predictable.

    Stick it somewhere in the 10. private IP space block and any code injection not also stumbling on the correct URL and will instead get a "Server not found" error.

    This will vastly reduce the chances of getting hit by any future as of yet undiscovered security problems using a URL, updated patches or not.
    • An easy work around for this is make the router URL IP address on the LAN side not easily predictable.

      Both the LAN and WAN IP addresses can be used to access the router's interface, and the WAN IP is not a secret to the attacker.

  • I went over the details one thing I am confused about is in this situation is the internal or External IP of the router that is Key here?

  • by RomulusNR ( 29439 ) on Friday July 24, 2009 @04:23PM (#28813061) Homepage

    It would be nice to know if this affects DD-WRT boxes that are not WAN-facing and are not in router mode.

    I have three DD-WRT's in client bridge mode so as to provide wired connections throughout the house. They hop over WiFi to the WAN-facing router which still runs stock VxWorks. So I'd be inclined to think that my boxes are safe.

    As for DD-WRT releasing a patch, gee thanks. I have two different (and old) versions of DD-WRT among the three devices and haven't touched them since installing, because upgrading requires lots of personal time with each device to reinstall and reconfigure and god knows what else and I simply don't have the time -- the whole point of setting up client bridges was to make life easier, not some sort of time-consuming exercise in obscure geek cred.

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