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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"
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
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.
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
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.
www.eFax.com are spammers
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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
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."
... 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
I was running Safari 1.2.3 (v125.9) which isn't quite the current version, but pretty close.
I can confirm this works when the "Block Pop-up Windows" in the Safari menu is disabled, but not when the Blocking option is enabled. Rather than just a "me too", I went through the demonstration in reverse order of the previous poster (and was careful to refresh and follow the appropriate links) so I don't think this behavior is due to caching issues.
While I do hope there will be a fix for this soon, IMHO, the more appropos fix is that secure sites should not EVER rely on popups.
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.
It is vulnerable, but not when you open the link in a new tab, only when you open a new window. So when you enable Single Window mode, you should be pretty safe.
Malicious site? All you need is to compromise or hijack (DNS etc) the relevant banner ad site or partner site.
Has happened before.
Users may still have to click something, but they could easily be tricked into doing that. Most users aren't constantly vigilant and observant. If the compromised banner ad opened another window that looked like Citibank's site whilst you were using Citibank's site, you could fall for it - especially since Citibank does use pop-ups.
Client-side verification This includes validating that all the fields in a form are filled in, as well as checking that the user entered the correct password. Naturally, this is the silliest reason to require Javascript, as the validation step still has to be done on the server side anyway, making the client-side validation a redundant convenience at best, and an addle-brained sign of utter incompetence at worst.
Just what I want.. a user posting 300 times before realizing that, yes, they must fill out the form. Think about something like Yahoo mail. I can go into a new message and if I forget to put in a To:, it will still post to the server and come back and say that I'm a moron. With JS verification, I would know instantly.
Obviously client-side verification shouldn't be used for passwords, but checking that a form is at least completely filled out is very helpful, both as a designer and a web user. Client side verification is practically instant and does not burden the server with incomplete requests. Of course, client side verification does not exempt you from having to perform server side verification.