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.

Popular Stories

ios 26 1 slide to stop

iOS 26.1 Brings Back 2007 Feature in New Way

Friday October 31, 2025 1:40 pm PDT by
The upcoming iOS 26.1 update includes a small but helpful change for iPhones, and it could prevent you from running late to something important. Specifically, when an alarm goes off in the Clock app, there is a new "slide to stop" control on the screen for turning off the alarm. On previous iOS 26 versions, there is simply a large "stop" button, which could be accidentally tapped. The new ...
M5 MacBook Pro

Waiting for New Macs? Apple Just Shared Bad News

Friday October 31, 2025 7:32 am PDT by
Apple has just given a strong indication that it will not be releasing any additional new Macs for the remainder of the year. Apple's CFO Kevan Parekh dropped the hint during the company's earnings call on Thursday:On Mac, keep in mind, we expect to face a very difficult compare against the M4 MacBook Pro, Mac mini, and iMac launches in the year-ago quarter.Parekh essentially gave a heads up ...
iPhone 17 Pro Cosmic Orange

8 Reasons to Wait for Next Year's iPhone 18 Pro

Thursday October 30, 2025 4:42 am PDT by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models at the same time, which is why we often get rumored features months ahead of launch. The iPhone 18 series is no different, and we already have a good idea of what to expect for the iPhone 18 Pro and iPhone 18 Pro Max. One thing worth...
iOS 26

6 New Things Your iPhone Can Do in iOS 26.1

Wednesday October 29, 2025 4:22 am PDT by
Apple is about to drop iOS 26.1, the first major point release since iOS 26 was rolled out in September, and there are at least six notable changes and improvements to look forward to. We've rounded them up below. Apple has already provided developers and public beta testers with the release candidate version of iOS 26.1, which means Apple will likely roll out the update to all compatible...
Apple Foldable Thumb

iPhone Fold: Launch, Pricing, and What to Expect From Apple's Foldable

Friday October 31, 2025 8:52 am PDT by
Apple is expected to launch a new foldable iPhone next year, based on multiple rumors and credible sources. The long-awaited device has been rumored for years now, but signs increasingly suggest that 2026 could indeed be the year that Apple releases its first foldable device. Below, we've collated an updated set of key details that have been leaked about Apple's foldable iPhone so far. Ove...
Coffee Burgundy and Purple iPhone 18 Pro Mock 1

Leaker Outlines Potential New Colors for iPhone 18 Pro

Friday October 31, 2025 8:28 am PDT by
Apple's iPhone 18 Pro models could be available in new rich and warm color option, according to a known leaker. The Weibo user known as "Instant Digital" today suggested that next-year's iPhone 18 Pro models will be available in at least one of the following color options: Coffee, purple, and burgundy. The iPhone XR, iPhone 11, iPhone 12, iPhone 14, and iPhone 14 Pro were all available in ...
apple tv hd

Apple Launched Its Big New Vision for TV 10 Years Ago Today

Thursday October 30, 2025 8:58 am PDT by
Apple launched the Apple TV HD, the Siri Remote, tvOS, and their accompanying App Store a decade ago today, marking a major overhaul of the device. The new vision for the Apple TV was unveiled on September 9, 2015 during Apple's "Hey Siri" event in San Francisco, where CEO Tim Cook introduced the device with the statement, "The future of TV is apps." The announcement represented a major...
iOS 26

Apple This November: iOS 26.2 Beta, Rumored New Products, and More

Thursday October 30, 2025 12:42 pm PDT by
Tomorrow is Halloween, and then November is upon us. Below, we outline what to expect from Apple next month, as the slower holiday season approaches. Apple is expected to kick off November by releasing iOS 26.1, iPadOS 26.1, macOS 26.1, watchOS 26.1, tvOS 26.1, and visionOS 26.1. With beta testing now wrapped up, the updates will likely be released this Monday, November 3 or Tuesday,...
iOS 26

iOS 26.1 Coming Soon: New Features for Your iPhone and Release Date

Monday October 27, 2025 7:55 am PDT by
The upcoming iOS 26.1 update includes a handful of new features and changes for iPhones, including a toggle for changing the appearance of the Liquid Glass design, "slide to stop" for alarms in the Clock app, and more. Below, we outline key details about iOS 26.1. Release Date Given that Apple has yet to seed an iOS 26.1 Release Candidate, which is typically the final beta version, the...
maxresdefault

Apple TV 4K Could Still Launch Before 2025 Ends: All the Rumored Features

Monday October 27, 2025 4:51 pm PDT by
Apple is designing an updated version of the Apple TV 4K, and rumors suggest that it could come out sometime in the next couple of months. We're not expecting a major overhaul with design changes, but even a simple chip upgrade will bring major improvements to Apple's set-top box. Subscribe to the MacRumors YouTube channel for more videos. We've rounded up all the latest Apple TV rumors. ...

Top Rated Comments

soco Avatar
178 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
178 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
178 months ago
And just like that, the 5.1 Jailbreak was delayed another month. :(
Score: 9 Votes (Like | Disagree)
Small White Car Avatar
178 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
178 months ago
"Settings> Safari> Javascript > Off"

Thanks Porco. An easy fix until the next update.
Score: 5 Votes (Like | Disagree)
Hyper-X Avatar
178 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)