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Some Hotspot Operators Secretly Intercept, Insert Ads In Web Pages

An anonymous reader writes with this excerpt from the NYT's "Bits" column: "Justin Watt, a Web engineer, was browsing the Web in his room at the Courtyard Marriott in Midtown Manhattan this week when he saw something strange. On his personal blog, a mysterious gap was appearing at the top of the page. After some sleuthing, Mr. Watt, who has a background in developing Web advertising tools, realized that the quirk was not confined to his site. The hotel's Internet service was secretly injecting lines of code into every page he visited, code that could allow it to insert ads into any Web page without the knowledge of the site visitor or the page's creator."

31 of 273 comments (clear)

  1. Hasn't this been going on for a while? by readandburn · · Score: 5, Insightful

    I don't think this is news. (Yes, I must be new here.....)

  2. without the knowledge of the site visitor by xaosflux · · Score: 5, Informative

    Of course this is in no way limited to hotels, even ISP's have been shown to do this. Using Client-Server encryption like SSL should easily bypass that.

    1. Re:without the knowledge of the site visitor by GamerGirlie · · Score: 5, Interesting

      Of course this is in no way limited to hotels, even ISP's have been shown to do this. Using Client-Server encryption like SSL should easily bypass that.

      And that is easily bypassed by the ISP. For example when I try to login to slashdot and it changes from http to https, my ISP serves me their self-signed cert instead of Slashdot's real one. This way they are capable to intercept secure communications too.

    2. Re:without the knowledge of the site visitor by jonwil · · Score: 4, Insightful

      Care to tell me which ISP carries out such a man-in-the-middle attack on a secure web site so I can permanently blacklist them and any entity even remotely connected to them?

    3. Re:without the knowledge of the site visitor by mwvdlee · · Score: 5, Insightful

      Hmmmm, no... intercepting and changing internet packages is evil.

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  3. Yep. So use HTTPS-Everywhere. by khasim · · Score: 5, Informative

    Well, if you use Firefox that is.

    If the connection between you and the website is encrypted, no one can add code to it.

    1. Re:Yep. So use HTTPS-Everywhere. by Skapare · · Score: 5, Informative

      More than just porn sites do this. Many others, like LinkedIn, are more benign, just using your contacts list from your web email provider(s) to push you to find more people you know within LinkedIn. They don't spam or auto-add anyone. But it's still a concern. I use separate browsers for every signed-in site I visit, so LinkedIn can't get to my Gmail account, for example. I was prompted by LinkedIn to enter my password for those sites (I'd never do that). I don't know if they would prompt if the same browser instance was already logged in (I'd never do that).

      Browsers should, and maybe FF now does, firewall JS code and data by hostname. Of course that would break using alternate servers for things like static images. But that's fixable by using the base name (remove the "www" part if that's on the name), and allowing access to hostnames that have name components added in front. So site slashdot.org could access images.slashdot.org. But tech.slashdot.org cannot access images.slashdot.org but can access images.tech.slashdot.org (so all sites just need to make their auxiliary servers named as child hostnames of the base hostname). The same wall should apply to Java and Flash, too (in addition to walls blocking access to the filesystem except as configured to be allowed into specific areas).

      I've not done any tests of such security in FF, Chrome, or any other browser. Have fun.

      --
      now we need to go OSS in diesel cars
  4. Captive Portals Do That You Know? by TemplePilot · · Score: 4, Interesting

    Thats right Captive Portal operators routinely inject advertisements either for their own operations or to suplement the donation button's found on the captive portal login at coffee shops, hotels and so on. Its a fairly common way to monetize what to a consumer might just be a temporary waystation to access the internet for free an hour or so. Often once some kind of payment has been tendered those 'ads' can be made to go away by the captive portal operator if they so choose. Sometimes CPO's even drop people into a walled garden featuring local businesses so you can freely web-shop the neighborhood once your free 2 hours is up. So you either pay or wait 24 hours when the captive portal resets. Usually a captive portal is a combination of server-router-software solutions and they don't exactly come cheaply irregardless what you might've been led to believe. Its an interesting side business if you have the time and witherwhal.

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    This strange comment at the bottom of the message is illogical.
    1. Re:Captive Portals Do That You Know? by eht · · Score: 3, Informative

      Hint, that is a word. From Merriam Webster

      http://www.merriam-webster.com/dictionary/irregardless

      "The most frequently repeated remark about it is that âoethere is no such word.â There is such a word, however."

      Just because you choose to not recognize it, even though you understand perfectly what he meant by it, shows your ignorance. By the way, ain't is a word too, well a contraction at any rate.

    2. Re:Captive Portals Do That You Know? by mikkelm · · Score: 3, Interesting

      So you're asking him to learn how language works because he objects to people who make up contradictory words as a consequence of apparently not understanding how the language that they're using works. I don't generally have a problem with new words to explain new concepts, or even new words to explain existing concepts, but making up a new word consisting of an existing word with the same definition, preceded by a prefix that typically serves to negate the following word, that's just.. well.. dense.

      Wouldn't it be easier if people just used the right words?

  5. I'm sure he agreed to this in the TOS. by Vandil+X · · Score: 3, Informative

    Whether it's free Wi-Fi or paid Wi-Fi, read those Terms of Service. I'm sure this activity was disclosed in theire either explicitly or with ambiguous language. As the saying goes: Don't like it? Don't use it.

    --
    Up, Up, Down, Down, Left, Right, Left, Right, B, A, START
    1. Re:I'm sure he agreed to this in the TOS. by Chrisq · · Score: 3, Interesting

      Whether it's free Wi-Fi or paid Wi-Fi, read those Terms of Service. I'm sure this activity was disclosed in theire either explicitly or with ambiguous language. As the saying goes: Don't like it? Don't use it.

      Where would you draw the line?

      Adding adverts for their hotel?
      Switching adverts for other hotels to theirs?
      Removing negative reviews of their hotel, or changing the rating?
      Removing news items supporting a political party the owners don't favour?
      Adding fictitious negative news stories about a political party the owners don't favour?

      In my view as soon as you start delivering content that has been changed from that the original author intended (except under complete control of the user such as adblock) then you are on dodgy ground.

  6. Re:Insert this: by Amyntas · · Score: 4, Funny

    Contrary to popular belief, a recent study has found that, 'First,' actually comes before second, and is generally regarded as something that should not be mistaken with second.

    Remember, One comes before Two comes before 60 comes after 12 comes before Six Trillion comes after 504.

  7. Copyright infringement? by Filter · · Score: 3, Interesting

    Wouldn't this be copyright infringement? The web page as you intended is your creative work, they are altering and distributing your work. I don't think you are allowed to do that.

       

    --

    "better ways of doing things eventually just replace the inferior things" - Linus Torvalds 09-08-07

  8. It's a copyright violation. by sotweed · · Score: 4, Insightful

    IANAL, and I don't play one on TV, but it seems pretty clearly a violation of a web site's copyright to do this. A web page
    is a visual work, and at least for any country that is party to the Bern Convention (this includes the US and most or all of Europe),
    a page is copyright even if it doesn't say so. So for the hotel or ISP to modify the page, especially when it is being paid to do so,
    seems a clear violation. Some web site should make a big stink (lawsuit!) about this and put an end to the practice. I think it wouldn't
    be a difficult case to win, particularly with all the other copyright enforcement actions going on (MPAA, etc.).

    I wonder if a similar case can be made for organizations like health clubs that show TV programs at the wrong aspect ratio, making
    people look as if they're 20% fatter (wider) than they actually are...

  9. Re:Yay a New Arms Race! by History's+Coming+To · · Score: 5, Interesting

    There's a simpler solution - if I write a web page and somebody copies all of my text and graphics as part of an advert (without my permission) then it's a fairly clear copyright infringement. So if you find a hotspot doing this just navigate to one of your own web pages and then sue the operator for copying your work and serving it up as an advert.

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    Please consider this account deleted, I just can't be bothered with the spam anymore.
  10. Re:HTTP Policies by icebike · · Score: 3, Interesting

    Does anyone know if SSL solves the problem? Can a malicious endpoint act as a proxy so the SSL connection is between the endpoint and the real site and then serve you a different SSL certificate with the adverts included. (Although I doubt they can make a certificate look like the legitimate website.) Alternatively they could just drop everything down to HTTP...

    They might be able to pull this off, but the revenue they could earn off of such a scheme would never pay the lawyer bills. One could argue this would be a DMCA violation. (In fact, they seem to be on shaky legal ground altering un-encryption streams. It is after all, a form of scraping and perhaps copyright violation.)

    The drop everything to HTTP would certainly be noticed.

    --
    Sig Battery depleted. Reverting to safe mode.
  11. VPN by SuperTechnoNerd · · Score: 3, Insightful

    So set up an encrypted tunnel to your home machine and set it up so you can browse the web through the tunnel as if you were at home. Slower perhaps, but worth it. If they are injecting stuff, then what else are they doing? Looking at your traffic?

  12. Re:HTTP Policies by bbecker23 · · Score: 5, Interesting

    Does anyone know if SSL solves the problem? Can a malicious endpoint act as a proxy so the SSL connection is between the endpoint and the real site and then serve you a different SSL certificate with the adverts included. (Although I doubt they can make a certificate look like the legitimate website.) Alternatively they could just drop everything down to HTTP...

    I've seen some novel approaches to working around SSL but most will tip off the end-user. I run a throttled honeypot on my home network with some ad-injection. I get a couple dollars a month from it, the neighbors get free internet, and it seriously cut-down on the number of auth-attempts against the secured side of my router. Most of the injectors just catch and sniff packets for webpages (trying to inject into, say, SSH would bork everything) and inserts an ad frame. I'll have to test how my setup handles a secured session but I've seen instances of SSL sessions being wrapped in a framed unsecured page (mostly at hotels and airports). Newer browsers (Firefox and Chrome anyway, no Windows box to test on) will pitch a fit about this but if you're connecting to an unsecured network, I doubt security is much of a priority.

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  13. Re:HTTP Policies by mwvdlee · · Score: 5, Insightful

    It isn't so much scraping as it is simply taking somebody's website content and copying it for their own profit.
    Plain and simple copyright violation where the website owner is the victim.

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  14. HTML modification going on since 2007 or earlier by ODBOL · · Score: 3, Interesting

    In November 2007, I bought a wireless box from Meraki (http://www.meraki.com/). I intended to use it to provide a free wireless hotspot for my neighborhood, and to be ready to peer with any neighbor who chose to work on the grassroots network. These were primarily symbolic acts, since neither service is likely to get much use in my neighborhood.

    In most respects, the Meraki box appeared to do a good job of exactly what I wanted. But I noticed a little blank stripe at the top of Web pages. I found that Meraki hacked HTTP packets to add that stripe. As owner, I was able to set the contents of the stripe (e.g., to advertise myself as the provider of the free hotspot, or to ask for payment if it's not free). But, I was not able to eliminate the stripe. I called support, and they confirmed that the stripe is not optional, but its contents are owner controlled. I sent the box back for a refund. I understand why Meraki provided the feature (I don't like it, but I understand). I don't understand why they made it impossible to turn it off. They were very good about delivery, support, and refund in all other respects.

    I think that Open Mesh (http://www.open-mesh.com/) provides something like the Meraki box, but cheaper and transparent to all Internet traffice. I have not tried their products yet.

    For the time being, I just leave my Tomato (http://www.polarcloud.com/tomato) box unprotected, and I think that people occasionally park in front of my house to use the network. But there's no chance of peering to help avoid the last-mile bottleneck.

    --
    Mike O'Donnell http://people.cs.uchicago.edu/~odonnell/
  15. Let's just be clear about that. by khasim · · Score: 5, Informative

    And what if they own one of the large CAs?

    Just to be clear about that ...

    You're postulating a situation where:
    The ISP
    is owned by a certificate authority
    that is, by default, trusted by your browser vendor
    and that certificate authority
    is creating certificates for 3rd party websites
    without the 3rd party websites' permission
    in order to facilitate man-in-the-middle attacks
    so that the ISP can inject ads into your session.

    I would imagine the backlash would kill both the ISP and that certificate authority.

  16. Re:HTTP Policies by SuricouRaven · · Score: 4, Insightful

    Stop thinking like an engineer, and lower yourself to the thoughts of a typical computer user.

    "A weird box just popped up! IT says something about certificates and signing, whatever that means. If I click 'accept' I'll get to see the website, so I'll do that."

  17. Re:Yay a New Arms Race! by 93+Escort+Wagon · · Score: 5, Interesting

    There's a simpler solution - if I write a web page and somebody copies all of my text and graphics as part of an advert (without my permission) then it's a fairly clear copyright infringement. So if you find a hotspot doing this just navigate to one of your own web pages and then sue the operator for copying your work and serving it up as an advert.

    Or, better yet, send an email to each significant site you've visited while at Marriott and tell them what's going on. It's likely they've got deeper pockets than you do. Most probably won't bother to go after the hotel; but it only takes one.

    --
    #DeleteChrome
  18. Re:HTTP Policies by Restil · · Score: 3, Informative

    While they couldn't insert code into an encrypted session, they COULD perform a man in the middle attack and accomplish the same thing, provided the user decided to override the certificate warning (which I'm guessing most people would). A more secure solution would be to do all the browsing over a ssh tunnel. That too could be intercepted, but it's less likely, and ssh will catch such an attempt provided the tunnel was first initiated over a trusted connection, so at least you'd be able to avoid using the service if you know it's going to be insecure.

    What's ironic is the fact that the cheap hotels that are out in the middle of nowhere have great, highspeed, well covered wifi with mostly unrestricted or completely unrestricted hotspots (most of the time, all you have to do is agree to a clickthrough agreement, and you're good to go). But go to a big hotel in the city for a convention or something and they want to charge $15 a day for it. I'd just grown accustomed to tethering my cellphone in those instances since I got higher speeds from that than I did from the hotel wifi.

    -Restil

    --
    Play with my webcams and lights here
  19. Re:HTTP Policies by Skapare · · Score: 3, Informative

    Does anyone know if SSL solves the problem? Can a malicious endpoint act as a proxy so the SSL connection is between the endpoint and the real site and then serve you a different SSL certificate with the adverts included. (Although I doubt they can make a certificate look like the legitimate website.) Alternatively they could just drop everything down to HTTP...

    The SSL layer already knows the hostname of where it wants to go. The signed certificate received from the connected server should have a cert for the Certificate Authority, identifying which public CA key to get from the collection the browser or SSL library has. The CA signature of the web site's cert is decrypted by that public CA key. If that works, it is then known the site cert is signed. If the site name also matches (maybe with wildcard enabled), and today's date is in the range valid for the signature, then the site cert is valid. Otherwise not, and you get that annoting security popup.

    For the proxy to insert anything, it would have to act as the end point for the SSL stream. But that setup would fail unless the proxy has the web site's certificate signed by a valid CA. If you add a new CA the proxy server used (its own), then it could do that. Otherwise they would have to convince some CA to sign certs for ALL the major sites, for use in this proxy. A bad CA could do this. You can then defeat that by removing the bad CA cert from your browser. But the hotel could defeat you by convincing you to add their local CA cert to your browser (and then the proxy can dynamically generate a fake signed cert for any site you visit if they know the name in advance, which can be done with a name server injection). You can defeat that by not allowing any of their stuff into your computer.

    If you have the means, a VPN to your own trusted network can help, though you then have slower responses. Test their network to see if you can access secured services you normally do have access to, like SSH, IMAPS, Submit/TLS. Also check to see if they have IPv6 and complain if not. Tell them "the FREE porn sites are on IPv6 only".

    --
    now we need to go OSS in diesel cars
  20. Re:That should fail. by Nikker · · Score: 3, Informative

    You should take a closer look at the CD media your ISP sends you to "setup" your Internet connection.

    --
    A loop, by its nature, continues. If that didn't make sense, start reading this sentence again.
  21. Re:HTTP Policies by Alex+Belits · · Score: 4, Insightful

    if you're connecting to an unsecured network, I doubt security is much of a priority.

    Congratulations, you are an idiot!

    The whole point of encryption is that it allows secure communications over insecure network.

    --
    Contrary to the popular belief, there indeed is no God.
  22. Re:HTTP Policies by colinrichardday · · Score: 4, Insightful

    You say that big-city hotels have higher costs, and that they charge more for wifi because of those higher costs (maybe not of bandwidth, but other stuff). You then criticize the GP for expecting prices to be higher based on costs? Hmm. . .

  23. Re:"Web Engineer?" by CohibaVancouver · · Score: 3, Informative

    I fail to see the problem here

    From http://en.wikipedia.org/wiki/Engineer

    In the US and Canada, engineering is defined as a regulated profession whose practice and practitioners are licensed and governed by law.

  24. Re:HTTP Policies by edb · · Score: 5, Interesting

    Without exception, in traveling to >30 hotels each year for the past [wayyy too many years], the higher the per-night rate for the hotel, the more the nickel-and-dime charges for what should be included as part of the accomodations.

    < $100/night usually includes:
        - FREE wifi, unspecified throughput, non-public IP
        - FREE incoming phone calls
        - FREE incoming faxes
        - FREE outgoing phone calls up to 30 min
        - FREE computer near lobby for guest use
        - FREE document printing for reasonable # pages
        - FREE microwave oven in the room
        - FREE mini-fridge in the room
        - FREE pillows & linens on the bed
        - FREE pull-out drying line for laundry in the bathroom
        - coin-op laundry for hotel guests

    > $100/night often imposes charges for:
        - WIFI: $12.95+tax per day
        - public IP: additional $10+tax per day
        - incoming faxes: $.50/page
        - outgoing phone calls: AT&T Operator rates + 200% surcharge
        - document printing: $.50/page
        - fridge in room: $25 per night, special request
        - microwave in room: $25 per night, special request
        - linens: changed every 3 days at no charge, no discount for multi-day stay
        - laundry: 24-48 hr turnaround; $5.00 per shirt, $10.00 per pants, don't even ask about other items!

    --
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