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

15 New Things Your iPhone Can Do in iOS 26.2

Friday December 5, 2025 9:40 am PST by
Apple is about to release iOS 26.2, the second major point update for iPhones since iOS 26 was rolled out in September, and there are at least 15 notable changes and improvements worth checking out. We've rounded them up below. Apple is expected to roll out iOS 26.2 to compatible devices sometime between December 8 and December 16. When the update drops, you can check Apple's servers for the ...
Intel Inside iPhone Feature

Apple's Return to Intel Rumored to Extend to iPhone

Friday December 5, 2025 10:08 am PST by
Intel is expected to begin supplying some Mac and iPad chips in a few years, and the latest rumor claims the partnership might extend to the iPhone. In a research note with investment firm GF Securities this week, obtained by MacRumors, analyst Jeff Pu said he and his colleagues "now expect" Intel to reach a supply deal with Apple for at least some non-pro iPhone chips starting in 2028....
ive and altman

Jony Ive's OpenAI Device Barred From Using 'io' Name

Friday December 5, 2025 6:22 am PST by
A U.S. appeals court has upheld a temporary restraining order that prevents OpenAI and Jony Ive's new hardware venture from using the name "io" for products similar to those planned by AI audio startup iyO, Bloomberg Law reports. iyO sued OpenAI earlier this year after the latter announced its partnership with Ive's new firm, arguing that OpenAI's planned "io" branding was too close to its...
iPhone 17 Pro Cosmic Orange

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

Monday December 1, 2025 2:40 am PST 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...
iPhone 14 Pro Dynamic Island

iPhone 18 Pro Leak Adds New Evidence for Under-Display Face ID

Monday December 8, 2025 4:54 am PST by
Apple is actively testing under-screen Face ID for next year's iPhone 18 Pro models using a special "spliced micro-transparent glass" window built into the display, claims a Chinese leaker. According to "Smart Pikachu," a Weibo account that has previously shared accurate supply-chain details on Chinese Android hardware, Apple is testing the special glass as a way to let the TrueDepth...
Photos App Icon Liquid Glass

John Gruber Shares Scathing Commentary About Apple's Departing Software Design Chief

Thursday December 4, 2025 9:30 am PST by
In a statement shared with Bloomberg on Wednesday, Apple confirmed that its software design chief Alan Dye will be leaving. Apple said Dye will be succeeded by Stephen Lemay, who has been a software designer at the company since 1999. Meta CEO Mark Zuckerberg announced that Dye will lead a new creative studio within the company's AR/VR division Reality Labs. On his blog Daring Fireball,...
maxresdefault

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

Monday December 1, 2025 3:00 am PST 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. Subscribe to the MacRumors YouTube channel for more videos. Below, we've collated an updated set of key details that ...
Johny Srouji

Apple Chip Chief Johny Srouji Could Be Next to Go as Exodus Continues

Sunday December 7, 2025 10:41 am PST by
Apple's senior vice president of hardware technologies Johny Srouji could be the next leading executive to leave the company amid an alarming exodus of leading employees, Bloomberg's Mark Gurman reports. Srouji apparently recently told CEO Tim Cook that he is "seriously considering leaving" in the near future. He intends to join another company if he departs. Srouji leads Apple's chip design ...
Apple John Ternus 2019

Will John Ternus Really Be Apple's Next CEO?

Friday December 5, 2025 9:01 am PST by
There is uncertainty about Apple's head of hardware engineering John Ternus succeeding Tim Cook as CEO, The Information reports. Some former Apple executives apparently hope that a new "dark-horse" candidate will emerge. Ternus is considered to be the most likely candidate to succeed Cook as CEO. The report notes that he is more likely to become CEO than software head chief Craig Federighi, ...
ios 18 to ios 26 upgrade

Apple Pushes iPhone Users Still on iOS 18 to Upgrade to iOS 26

Tuesday December 2, 2025 11:09 am PST by
Apple is encouraging iPhone users who are still running iOS 18 to upgrade to iOS 26 by making the iOS 26 software upgrade option more prominent. Since iOS 26 launched in September, it has been displayed as an optional upgrade at the bottom of the Software Update interface in the Settings app. iOS 18 has been the default operating system option, and users running iOS 18 have seen iOS 18...

Top Rated Comments

soco Avatar
179 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
179 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
179 months ago
And just like that, the 5.1 Jailbreak was delayed another month. :(
Score: 9 Votes (Like | Disagree)
Small White Car Avatar
179 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
179 months ago
"Settings> Safari> Javascript > Off"

Thanks Porco. An easy fix until the next update.
Score: 5 Votes (Like | Disagree)
Hyper-X Avatar
179 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)