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New Vulnerability Affects All Browsers

Jimmy writes "Secunia is reported about a new vulnerability, which affects all browsers. It allows a malicious web site to "hi-jack" pop-up windows, which could have been opened by e.g. a your bank or an online shop. Here is a demonstration of the vulnerability"

38 of 945 comments (clear)

  1. All your typos... by Indy+Media+Watch · · Score: 4, Funny

    Jimmy writes "Secunia is reported about a new vulnerability"

    And in other news, Slashdot is reported all about a new grammatical error in the headlines.

    Reporting anyone?

    --

    Indy Media Watch-Proctologist of the Internet

    1. Re:All your typos... by NMerriam · · Score: 4, Funny

      Grammatical errors on Slashdot? That's unpossible!

      --
      Recursive: Adj. See Recursive.
  2. no problem here... by jxyama · · Score: 4, Informative

    mac os x 10.3.6... running safari 1.2.4 (the latest build.)

    1. Re:no problem here... by undertow3886 · · Score: 5, Informative

      No problem on Konqueror 3.3.1. On their site though, they said the Konqueror version they found the problem in was a 3.2 version.

      --
      Sick of people knocking on Gentoo's greatness in completely unrelated .sigs? Me too!
    2. Re:no problem here... by Too+Much+Noise · · Score: 4, Informative

      Exactly - in particular unchecking the "allow scripts to change images" option 'fixes' the problem (firefox 1.0)

  3. Safari test by sg3000 · · Score: 4, Informative

    I tried the test in Safari 1.2.4 under Mac OS X 10.3.6. I had pop-ups blocked, the normal way I set my browser. Doing the test, I saw the Citibank site fine. When I clicked on the "Consumer Alert" button, it looked like the regular Citibank content. No problem there. I refreshed and clicked on the other "try this test" link, and there still was no problem.

    When I turned off the pop-up blocking feature, then when I tried the test, I did see a pop-up from the Secunia site instead of the Citibank text. Now that's a problem.

    Clearly, this is just another reason to block pop-up windows.

    --
    Insert simplistic political, ideological, or personal proselytization here.
  4. Re:I don't get it by Caine · · Score: 5, Informative

    Did you actually follow the instructions? That is: Did you click on the image on the citibank-page, thereby giving you a third window? It doesn't sound like it from your comment.

    And the exploit worked just 'fine' on my firefox 1.0.

  5. Re:Sniff, our little browser's all grown up... by Indy+Media+Watch · · Score: 5, Insightful

    Now we can move from the myth that free software is impervious to exploits

    Uh, who was saying that?

    --

    Indy Media Watch-Proctologist of the Internet

  6. All browsers?!? by localman · · Score: 4, Funny

    I just don't believe it. Anything -- even an exploit -- working in all browsers would be unprecedented!

  7. jack pot by loid_void · · Score: 4, Funny

    i did it using safari, got citibank, i have no account but was able to transfer $100 million into an offshore account. That was some test

    --
    Anyone seen my jagged little pill?
  8. Re:Sniff, our little browser's all grown up... by Frogbert · · Score: 4, Insightful

    What are you talking about? Firefox has always had bugs, why do you think we get security updates? The difference, as we will soon see, is that the Firefox will have a patch weeks, or perhaps months before IE.

  9. Re:I don't get it by Frizzle+Fry · · Score: 4, Informative

    The fact that everyone is confused is an indication that their instructions suck. "Step one" is click on a link in the citibank site that you haven't visited yet. "Step two" is actually visiting the citibank site. And then "step three" is a no-op; the space for that step is instead used to discuss whether you are vulnerable. (Presumably, step five is "profit!!!"). Who came up with this and what planet are they from where this is a logical sequence of instructions?

    --
    I'd rather be lucky than good.
  10. Not the first Firefox vulnerability by Chuck+Chunder · · Score: 4, Informative

    The first since 1.0 maybe, but certainly not the first outright.

    As far as I can tell the problem is fixed in the latest Opera beta so they might be able to get it into a proper release pretty soon too.

    --
    Boffoonery - downloadable Comedy Benefit for Bletchley Park
  11. Re:Sniff, our little browser's all grown up... by kaiser423 · · Score: 4, Funny

    No, it's still impervious, the exploit didn't work on my system. Sorry, OSS still has a 100% perfect, virignal, like freshly-fallen snow track record. /sarcasm No one ever said any of those things, and I doubt that anyone believes them, so get off your high-horse.

  12. Re:It doesn't affect Safari by narratorDan · · Score: 5, Informative

    Actually it does effect Safari, but you have to jump through hoops to get it to work.
    After you have clicked on the link, you have to refresh the Secunia page, then it will work. It's kinda strange, but I guess it is a vulnerability. Kinda like walking back and forth through a bad neighborhood while counting your cash.

    NarratorDan

    --
    "If you're not confused by quantum mechanics, you really don't understand it." - Niels Bohr
  13. Re:Doesn't work for me by TheViciousOverWind · · Score: 4, Informative

    Funny, I've tried this in Internet Explorer 6.0 and Mozilla 1.7, but I could only get it to "work" in Mozilla.

    In Internet Explorer I pressed "With popup-blocker" (Google Toolbar) and up came Citibank, then I pressed the Fraudulent E-Mail button, and up came CitiBanks popupwindow, first when I closed the popupwindow the "This was hijacked" window appeared (as if triggered by the window.onclose function) but that does not strike me as a gigantic security-hole.

    Of course the issue in itself is scary, but I'm confident the Mozilla team will have a patch out in no time.

    This should probably serve as a reminder to webmasters out there, that if you want users to trust content you provide in popup-windows eg. for creditcard payments, you should provide the address-bar, and if the creditcard processing takes place on another server, explain to the customer before he clicks "pay by creditcard" why the window will load from another server.

    --
    My <1000 UID is with a hot chick
  14. Here's how it works by sbszine · · Score: 5, Insightful

    The links to Citibank from the Secunia site are actually handled by JavaScript. The script sets a timer, then opens citibank. Every second or so, Secunia's script then checks whether you've opened Citibank's pop-up. If you have, it opens a window with the same name (i.e. variable name) as Citibank's window, thus overwriting their content.

    So the attacker doesn't need you to click on anything, they just need you to have their site open -- with the timer going -- in another window. Also, the attacker needs to know in advance what name the victim site's pop-up is referenced by. A dynamically generated name could possibly defeat this attack, though the attacker could always crawl the DOM for a handle to the pop-up.

    --

    Vino, gyno, and techno -Bruce Sterling

  15. I think I've solved it. by khasim · · Score: 4, Informative

    FF 1.0 on Win2K.

    Middle-click to open citibank page in new tab YOU WILL NOT BE VULNERABLE.

    Left click and allow citibank page to open in new window YOU WILL BE VULNERABLE.

    At least, that's the behaviour I see on this box.

  16. Once again, why needless use of Javascript is BAD! by wowbagger · · Score: 4, Insightful

    This all boils down to a Javascript vulnerability.

    If web masters would stop NEEDLESSLY using Javascript to do things like open new windows, and would use it ONLY when there is no way using HTML to accomplish the same goal, then people would not need to have Javascript active all the time, and the impact of exploits like this would be greatly reduced.

    If, instead of using <a href="#" onclick="foo"> or <a href="javascript(foo)"> type constructs, web designers would use <a target="_blank" href="something.html" onclick="javascript(stuff)"> type constructs, then if the user HAS Javascript active, then the web master can micromanage the newly created window. If not, then the user STILL gets a new window, just not one that the web master can remove all the chrome from.

    Seriously - when was the last time you heard of an exploit that used straight HTML? All of the recent exploits in ALL browsers, IE included, have been in either Javascript or Active-X, not in the core HTML rendering.

    There is a REASON for that.

  17. Re:All browsers?!? by El+Cubano · · Score: 5, Funny

    I just don't believe it. Anything -- even an exploit -- working in all browsers would be unprecedented!

    Lynx appears to be unaffected.

  18. Of course it's a bug by Chuck+Chunder · · Score: 5, Insightful

    Target names should only exist within the namespace of the site that created them.

    Site A should be able to create and interact with a window named "popup".
    Site B should be able to create and interact with a window named "popup".
    This should happen without either site interfering, blocking or overwriting the other. They should simply be invisible to each other, existing in completely seperate little worlds.

    --
    Boffoonery - downloadable Comedy Benefit for Bletchley Park
    1. Re:Of course it's a bug by Anonymous Coward · · Score: 5, Insightful

      OF course that seems sensible. But when you say "should" do you mean "should" because you think so, or because some W3C or other standard says so?

  19. Comment removed by account_deleted · · Score: 4, Informative

    Comment removed based on user account deletion

  20. Re:I don't get it by Jehlon · · Score: 5, Informative
    No kidding their instructions sucked. Here's a step-by-step:
    0. If you have not tried the test already, skip steps 1-3.
    1. Copy these instructions to Notepad.
    2. Close all browser windows.
    3. Open a new browser window to
    http://secunia.com/multiple_browsers_window_injec tion_vulnerability_test/
    4. Skip down to "Step 2" and click the link appropriate for your system. The vast majority of users will click on the link "Test Now - With Pop-up Blocker - Left Click On This Link".
    5. Click on the "Consumer Alert" image on the right of Citibank's page.
    If the exploit was successful, the pop-up window from Citibank will attempt to open a site from secunia.com. I don't know what that page looks like, only that their webserver didn't respond when I tried going there.

    I hope this helps the vast masses of smart /.'ers who don't care to take 10 minutes to decompile secunia's instructions.
  21. Mozilla/Firefox Workaround by loconet · · Score: 5, Informative

    According to MozillaNews the following work around can be applied to Mozilla/Firefox:

    1. Enter about:config in the Location Bar.
    2. Enter dom.disable_window_open_feature.location in the filter field.
    3. Right-click (Ctrl+click on Mac OS) the preference option and choose Toggle (the value should change to true).

    This issue is already being worked on bug 273699 (copy link location, paste) filed a few hours ago.

    As a side note, being able to see the bug fixing progress unfold is one of the many reasons why i love open source. I am able to learn so much from just seeing the process take place from start to finish, how it is reported, test cases created, problems that arise, insights into other parts of the system, who the people involved are, reviews, patches, etc.

    --
    [alk]
    1. Re:Mozilla/Firefox Workaround by thomkt · · Score: 5, Informative

      This doesn't prevent the pop-up hijacking from happening; it forces the address bar to display, so you can see the location of the pop-up.

      From the page:

      "Note that, although the attack site can inject its own content, it cannot change the URL appearing in the Location Bar. Firefox and Mozilla have the ability to deny access to the Location Bar so all pop-up windows always have it."

    2. Re:Mozilla/Firefox Workaround by Fnkmaster · · Score: 4, Insightful

      All these damned Secunia bugs are basically human error bugs anyway. If you know what's in the popup, it's impossible to be spoofed - if the URL bar shows a site that's not what you expect, close it.

      In general, it's always going to be possible if you are browsing sketchy and secure sites at the same time that the sketchy site might pop up some deceptive window, and if you are confused, and can't see the URL bar, you might think it came from the secure site, with or without this specific injection issue. Which is why this workaround out to be default behavior anyway (I HATE sites that try to hide my location bar and navigation toolbar, those bastards).

      Anyway, the point is, yes the issue should be fixed, but if you applied the workaround, it makes the exploit essentially worthless to an adversary.

  22. Re:Once again, why needless use of Javascript is B by dghcasp · · Score: 4, Insightful
    And this is part of a larger user interface principle, "Don't try to control your user's behaviour if you don't need to."

    Example: Sites that pop up their "main" window from their "entry tunnel." Exactly what justification do you have for thinking I still need to view your entry tunnel?

    Example: (as mentioned,) sites that use Javascript to open windows. Granted, this practice came around before Opera/Mozilla introduced us to the wonders of tabbed browsing, but what's the point of pulling up a "diversionary" window and forcing the user to close it? Afraid they might not understand the concept of the "back" button?

    Example: using flash/java/shockwave/etc to perform functions that could be handled in HTML, especially now that we have DHTML. I have trouble with understanding the argument "we will be more successful if we deny access to some percentage of the population."

    etc etc etc.IMHO, this is a symptom of the problem where people assume "everyone else thinks / acts / behaves in the same way I do."

  23. Re:Doesn't work for me by Atrax · · Score: 4, Insightful

    ... useless as blink tags.

    I disagree. I think they have their moments. Such as displaying incidental information without interrupting the flow of something you're already doing (say, a help link in a wizard-style sequence of pages)

    like everything else, popups are a tool which can be used or misused. Unfortunately they're mostly misused.

    --
    Screw you all! I'm off to the pub
  24. Re:I call bullshit!! by corbettw · · Score: 4, Informative

    Except that it would be easy to exploit this. Here's an example:

    1) Send out a phishing expedition, asking people to log into their BofA account to update their account information. Make it look real official, and include a link that goes to "https://www.bankofamerica.com". The new window takes them to the real site, encrypted and everything.
    2) Customers login and check their mailing address, or whatever.
    3) Some percentage of them will leave their windows open for more than 10 minutes, at which point BofA sends their standard pop-up window warning about account inactivity and logout.
    4) Hijack the pop-up window and do Something Nefarious, like initiate a funds transfer.

    Now, this isn't a perfect example. But there are an untold number of different sites out there who use pop-ups for perfectly reasonable applications, and it would be trivial for some phisher to get people to go to those sites using his link.

    The best thing to do is, for those sites who use pop-ups to communicate with their visitors, use some nonstandard form for naming those windows. Use the person's username, a random string, a DES hash with the first two characters of the day of the week as the salt and the time the page is first loaded as the string, whatever (no, don't use "whatever", that's just a figure of speech)'

    --
    God invented whiskey so the Irish would not rule the world.
  25. You know you've found a good exploit... by Dipster · · Score: 4, Funny

    when it takes Slashdotters 5 minutes and other people's help to activate it...

  26. Re:I don't get it by megaversal · · Score: 4, Informative

    My fix is a little easier (in my opinion, only because I hate having another toolbar taking up desktop real estate)...

    under about:config, I have dom.disable_window_open_feature.location set to true. So every window must show the location (and because of it, I immediately could see the webpage I was at was not citibank.com).

    --
    Sig!
  27. Re:Once again, why needless use of Javascript is B by http · · Score: 5, Informative
    Nice try.

    1. 'target' is certainly part of standard html.
    http://www.w3.org/TR/html4/present/frames.html#ade f-target
    Just because it isn't defined initially by the A tag doesn't mean the A tag can't use it.

    2. From http://www.w3.org/TR/html4/types.html#type-frame-t arget:
    The following target names are reserved and have special meanings.
    _blank
    The user agent should load the designated document in a new, unnamed window.
    PS. Hey mods, if you don't know about a subject, don't mark a post 'informative' just because there's a link in it.
    --
    If opportunity came disguised as temptation, one knock would be enough.
    3^2 * 67^1 * 977^1
  28. This sounds scary by einhverfr · · Score: 4, Funny

    All browsers? Can someone tell me how to get this to work on Lynx?

    --

    LedgerSMB: Open source Accounting/ERP
    1. Re:This sounds scary by Curtman · · Score: 4, Funny

      Gentoo here as well. Looks like IE in Wine is vulnerable though. Way to go Wine team, great compatibility. :)

  29. Lynx support by nuntius · · Score: 4, Funny

    Rumor has it, patches to support this exploit in Lynx will be available by the end of the week. ;)

  30. Re:Once again, why needless use of Javascript is B by ubernostrum · · Score: 4, Informative

    Are you trying to imply that the thousands of XHTML Strict websites out there produced by web/graphic designers, web developers, bloggers, and those who are supporting the standards are doing something wrong?

    Yup. Check out Ian Hickson's "Sending XHTML as text/html Considered Harmful" for a quick primer on what most sites that do XHTML are doing wrong. Check out Evan Goer's list of "X-Philes" for a list of the very few sites which get it right, and his purge of sites from that list for an indication of how easy it is to go wrong even after you've initially gotten it right.

    As for HTML generally not producing good markup and being "too loose", I hate to break it to you but XHTML 1.0 and HTML 4.01 are element-for-element identical; the only difference between the two is that one is an SGML application and one is an XML application. And when you serve XHTML 1.0 as "text/html" (e.g., when you do XHTML the way ESPN and others do) you don't gain any of the strictness benefits of XML. And the only thing XHTML 1.1 does on top of that is deprecate a couple more things and add modularization and ruby support, so I'm really not sure where all the "good markup" would come from in a transition to XHTML. Plus there's no reason to believe that serving XHTML 1.1 as "text/html" is conformant, so if you use 1.1 you either break the spec or you shut out IE. Likewise, switching to an XHTML DOCTYPE and using XML syntax doesn't magically confer accessibility on a page; it's just as easy to write a horrid, bloated, table-based images-for-everything page in XHTML as it is in HTML 4.01.

    I suspect that you're making a common mistake among people who've just discovered web standards: you're confusing XHTML with good markup and best practices (check out Molly Holzschlag on what standards are and aren't). Anyway, it's quite possible to write beautiful, clean, accessible, semantically rich HTML 4.01 with separation of content from presentation; after all, it's got the same set of tags and attributes as XHTML 1.0, so if you can do it in one you can do it in the other just as easily. And when you consider that serving valid, well-formed XHTML according to the spec can be a nightmare at times, it's no surprise that even "gurus" of the standards world (e.g., Mark Pilgrim, Anne van Kesteren) have gone back to or recommended sticking with HTML 4.01 unless you really need one of the features gained by an XML-based HTML.

    And lest you continue to think I'm some sort of skeptic or enemey of web standards, well, every site I've built in the past three years (basically, since I discovered there was such a thing as a "web standard") has been valid, accessible, and CSS-based. I just know from experience that valid markup and stylesheets are one part of the equation, and there are an awful lot of those "best practices" that aren't ever published in a spec from the W3C or anyone else.

  31. Re:Sniff, our little browser's all grown up... by mrogers · · Score: 4, Informative
    Yes, the bug is in Javascript rather than the browser, but that doesn't mean specific Javascript implementations can't be fixed. You could, for example, only allow scripts to modify windows originating from the same domain as the window running the script. Actually I thought this was already the case, but I guess there's a loophole where popup windows are concerned.

    BTW Javascript has nothing to do with Java except the name.