Feeds

Google Marketplace DRM broken

Androids can be pirates too

Intelligent flash storage arrays

Android applications secured by Google's Library aren't as secure as they should be, with only a byte or two preventing applications being copied freely.

The bytes in question are contained within the selected application but clearly identifiable once the app has been disassembled, as demonstrated by Justin Case, whose write up on Android Police suggests that the process could easily be automated.

Android applications exist in byte-code, as do Java apps, and can thus be disassembled back to something very close to the original source with surprising ease. All the pirate has to do is disassemble the application, change how it responds when told that there isn't a valid licence, then recompile it and Bob's your pirate.

Applications protected by Google's License Verification Library (LVL) communicate with the Marketplace application on the phone, which connects to Google's Marketplace Server to confirm the application is licensed. The Marketplace application returns a "1" if the application isn't allowed to run, so on receiving a "1" the application displays some information to that effect and quits. But that decision tree can be changed so an application receiving a "1" decides instead to go ahead and run, as demonstrated in this video:

Not all developers use LVL - there are many alternatives - but LVL is easy to implement and locks applications to a Google cloud identity, allowing users to take applications with them when upgrading handsets.

Developers might also implement a less obvious decision tree - Java developers regularly use obfuscation tools to make their disassembled code hard to read (changing object and variable names, for example). That would make the task harder, but not impossible.

Occasional piracy can't be avoided - the idea is to make it sufficiently difficult to make most users opt for the paid alternative. Case reckons the process he demonstrates could easily be batched with a script, allowing a nefarious pirate to provide unlocked applications that could be installed by anyone without technical knowledge - at which point it becomes a more serious issue.

Fixing this problem won't be easy - it's up to developers to process the response from the Marketplace application, which remains secure. Android code will always be open to disassembly, thanks to its use of the Java model. A lot will depend on how effective obfuscation turns out to be, and how many developers take the time to apply it. ®

Security for virtualized datacentres

More from The Register

next story
You! AT&T! The only thing 'unlimited' about you is your CHEEK, growl feds
Man, we did everything but knock on their doors - carrier
The DRUGSTORES DON'T WORK, CVS makes IT WORSE ... for Apple Pay
Goog Wallet apparently also spurned in NFC lockdown
Watch out, Samsung and Apple: Xiaomi's No 3 in smartphones now
From obscurity to selling 19 million mobes a quarter
Brazil greenlights $200m internet cable to Europe in bid to outfox NSA
Only one problem: it won't make the slightest difference. And they know it
Wanna hop carriers with your iPad's Apple SIM? AVOID AT&T
Unless you want your network-swapping tech disabled for good, that is
Knocking Knox: Samsung DENIES vuln claims, says mysterious blogger is a JOKER
But YES, system does store encryption key on the device
prev story

Whitepapers

Cloud and hybrid-cloud data protection for VMware
Learn how quick and easy it is to configure backups and perform restores for VMware environments.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
Website security in corporate America
Find out how you rank among other IT managers testing your website's vulnerabilities.