iOS 4 lock screen flaw grants access to contacts

There is a security flaw in iOS 4.1 that would allow someone to bypass the 4-digit passcode lock to access the Phone app

MacRumors reported today a security flaw in iOS 4.1 that would allow someone to bypass the 4-digit passcode lock in order to access the Phone app. While the home screen and other apps appear to remain secure, access to the Phone app is no small prize, granting the unauthorized user the ability to view or edit contacts and voicemails, as well as make non-emergency calls. You can also apparently start Voice Control to play music or *gasp* ask what time it is.

The passcode bypass bug can be reproduced by the following method: touch the Emergency Call button on the Enter Passcode screen. On the Emergency Call screen, dial a non-emergency number (such as '#'). Hit the call button immediately followed by the hold/lock button on the top of the phone.

The test video was done on a jailbroken iPhone 4 with iOS 4.1, though I've successfully reproduced the bug myself on a non-jailbroken iPhone 4. Forum posts have confirmed it also affects iPhone 3G and 3GS, as well as iOS 4.0.

Some might remember a similar bug in iOS 2.0.1 that allowed a user to simply double-tap the home button in the emergency call screen to access the Favorites list, which could easily link to the SMS, Maps, or Safari apps.

Hopefully the press this bug is receiving will lead to a speedy fix from Apple.

Follow Mike Keller and GeekTech on Twitter.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.

Tags mobileAppleiossoftwareapplicationstelecommunicationapple iphoneMobile operating systemsExploits / vulnerabilities

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Mike Keller

PC World (US online)
Show Comments

Cool Tech

Toys for Boys

Family Friendly

Stocking Stuffer

SmartLens - Clip on Phone Camera Lens Set of 3

Learn more >

Christmas Gift Guide

Click for more ›

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Michael Hargreaves

Microsoft Office 365/Dell XPS 15 2-in-1

I’d recommend a Dell XPS 15 2-in-1 and the new Windows 10 to anyone who needs to get serious work done (before you kick back on your couch with your favourite Netflix show.)

Maryellen Rose George

Brother PT-P750W

It’s useful for office tasks as well as pragmatic labelling of equipment and storage – just don’t get too excited and label everything in sight!

Cathy Giles

Brother MFC-L8900CDW

The Brother MFC-L8900CDW is an absolute stand out. I struggle to fault it.

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?