Feeds

Skype for iPhone makes stealing address books a snap

Just add JavaScript

Intelligent flash storage arrays

If you use Skype on an iPhone or iPod touch, Phil Purviance can steal your device's address book simply by sending you a chat message.

In a video posted over the weekend, the security researcher makes the attack look like child's play. Type some JavaScript commands into the user name of a Skype account, use it to send a chat message to someone using the latest version of Skype on an iPhone or iPod touch, and load a small program onto a webserver. Within minutes, you'll have a fully-searchable copy of the victim's address book.

“I'm going to send a user on an iPhone a message, and when he sees the message, the exploit will run,” the narrator says. “When the exploit code is run, the victim's iPhone will automatically make a new connection to my server to grab a larger payload instructing the victim's iPhone to upload its entire address book file to the server.”

The attack exploits two oversights that just go to show that even elaborately erected walled gardens such as Apple's can contain threats that menace its blissful inhabitants. The first is a failure by Skype to sanitize potentially dangerous JavaScript commands from the text that gets sent in chat messages. Skype for Macs recently succumbed to a similar XSS, or cross-site scripting, vulnerability that allowed attackers to commandeer a victim's computer simply by viewing a malicious message.

The other lapse making Purviance's attack possible was the decision by iOS developers to make the file storing address-book contents accessible to every app installed, including Skype. That means all that's required to steal a full list of contacts is to find and exploit a vulnerability in a single program installed on a victim's device.

In a Web 2.0 kind of world, contacts for many people aren't exactly closely guarded secrets. For many others – say, attorneys and people who work with survivors of domestic abuse – the names, addresses and phone numbers of contacts are sensitive information.

It's already been 48 hours since this vulnerability was first documented, and the vulnerable app is still available in the iTunes Store. It will be interesting to see how long it takes Apple and Skype to close the gaping hole. ®

Choosing a cloud hosting partner with confidence

More from The Register

next story
Knock Knock tool makes a joke of Mac AV
Yes, we know Macs 'don't get viruses', but when they do this code'll spot 'em
Feds seek potential 'second Snowden' gov doc leaker – report
Hang on, Ed wasn't here when we compiled THIS document
Why weasel words might not work for Whisper
CEO suspends editor but privacy questions remain
DEATH by PowerPoint: Microsoft warns of 0-day attack hidden in slides
Might put out patch in update, might chuck it out sooner
BlackEnergy crimeware coursing through US control systems
US CERT says three flavours of control kit are under attack
China is ALREADY spying on Apple iCloud users, claims watchdog
Attack harvests users' info at iPhone 6 launch
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Top 5 reasons to deploy VMware with Tegile
Data demand and the rise of virtualization is challenging IT teams to deliver storage performance, scalability and capacity that can keep up, while maximizing efficiency.
Mitigating web security risk with SSL certificates
Web-based systems are essential tools for running business processes and delivering services to customers.