Address Bar Security Issue Found in iOS 5.1 Safari

A security firm has discovered a security issue in the iOS 5.1 version of MobileSafari, the most recent version of the operating system that runs on millions of Apple mobile devices. The behavior was discovered and detailed by David Vieira-Kurz of MajorSecurity.net.

The weakness is caused due to an error within the handling of URLs when using javascript's window.open() method. This can be exploited to potentially trick users into supplying sensitive information to a malicious web site, because information displayed in the address bar can be constructed in a certain way, which may lead users to believe that they're visiting another web site than the displayed web site.

addressbarvul
To test it out, visit this demo page on an iPhone, iPod Touch or iPad running iOS 5.1. Click the 'Demo' button and MobileSafari will open a new window displaying "www.apple.com" in the address bar, though it's actually loading a page from MajorSecurity.net.

The security firm does note that Apple was informed of the vulnerability three weeks ago, and it is only being made public today. Apple acknowledged the bug and should be pushing a fix soon.

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Top Rated Comments

soco Avatar
173 months ago
Apple are getting a little slack:

1. Hot iPads
2. Wifi Issues On New iPad
3. Safari On Retina Ipad's not actually pulling the fullres wallpaper / images
4. Security issues within 5.1

Apple. You have a B- you can and should be doing a lot better than this!!
Sorry to break it to you, and I loved the man, but he passed away back in October. It's Tim & Co.'s company now and they, despite misinformation to the contrary, are having just as many (read: few) real issues as they did when Steve was around.
Score: 14 Votes (Like | Disagree)
doboy Avatar
173 months ago
Public Announcement:

ALWAYS enter the URL manually or use your own bookmark for ANYTHING remotely important. This also means DO NOT click on the links in your email from financial institutions, PayPal, etc.
Score: 10 Votes (Like | Disagree)
soco Avatar
173 months ago
And just like that, the 5.1 Jailbreak was delayed another month. :(
Score: 9 Votes (Like | Disagree)
Small White Car Avatar
173 months ago
That's a pretty good trick.

I mean, usually these things are like "if you download pirated software AND give it your password AND..."

But this one's pretty good. That, like, just worked.
Score: 6 Votes (Like | Disagree)
RVdave Avatar
173 months ago
"Settings> Safari> Javascript > Off"

Thanks Porco. An easy fix until the next update.
Score: 5 Votes (Like | Disagree)
Hyper-X Avatar
173 months ago
Approximately 100% of iOS users use Safari.

And how is it the worst? It's the best for Mac (idk about Windows). Even if you were going to say it was worse than FireFox or something, Internet Explorer is undoubtedly the worst on any OS.
I typed that comment on iOS and it wasn't on Safari but rather iCab. In fact my MacBook doesn't use Safari by default. I understand why iOS and Mac users use Safari because it comes with it by default, the same reason why there's so many IE users on Windows. My Windows computers have never seen Safari installed in a very long time.

For a Mac I'd argue that Chrome is superior but that's not to say it's the perfect browser either. Firefox is too intrusive with all the warning messages like Vista and really relies on 100% user input to make decisions. IE9 has come a long way, it's actually one of the fastest and safest browsers to be used on Windows machines.

For mijail, yes I'm aware of that it's about Mobile Safari however Safari in itself is very late to the game, they introduced sandboxing years after Google's been doing it with Chrome. There's a lot of great extensions and plugins for Chrome and Firefox but Safari's seriously lacking compared to the other 2.
Score: 4 Votes (Like | Disagree)