Feeds

Crypto boffins uncover rogue task risk on Amazon cloud

AWS drops the SOAP, plugs backdoor quickly though

Boost IT visibility and business value

Security researchers have unearthed a flaw in Amazon Web Services that created a possible mechanism for hackers to take over control of cloud-based systems and run administrative tasks.

The flaw, which affected Amazon's EC2 cloud and has already been plugged, could have been abused to start and stop virtual machines or create new images in an EC2 virtual environment, for example. The root cause of the security weakness stemmed from poor cryptographic practices.

A team of researchers from Germany's Ruhr University found that an XML signature-based attack can be used to manipulate SOAP messages in such a way that EC4 authentication systems fail to detect that they have been doctored – and thus action them as authentic.

The approach applies a class of security shortcoming, involving the modification of partially signed XML documents, that was first uncovered in 2005 as affecting cloud-based systems, H Security reports.

The attack was possible because application signature verification and XML interpretation were handled separately by Amazon's SOAP interface, a security shortcoming that allows unsigned code to be smuggled through gateways onto management systems via maliciously modified messages. "Attackers can move the signed partial tree and then inject specially crafted elements in the original location," H Security explains.

Eucalyptus, an open source-based framework for creating private cloud installations, was similarly vulnerable, according to the Ruhr team.

In an academic paper, the researchers suggest a fix for these so-called signature-wrapping attacks that involves using a "subset of XPath instead of ID attributes to point to the signed subtree", an approach they reckon is both more efficient and secure.

The researchers said Amazon was also vulnerable to cross-site scripting (XSS) attacks that could have allowed users logged onto its online store to hijack an AWS session, using injected JavaScript code. The researchers demonstrated the vulnerability, only possible because signing into Amazon store automatically creates a concurrent AWS cloud service session automatically, at an ACM workshop on cloud security during a presentation entitled All Your Clouds are Belong to us.

The researchers informed both Amazon and Eucalyptus developers of the security flaws prior to their presentation. Both Amazon and Eucalyptus have reportedly fixed the flaws.

More details on the cloud security aspect of their research can be found in a statement by the Ruhr team (in German) here. ®

The essential guide to IT transformation

More from The Register

next story
The Return of BSOD: Does ANYONE trust Microsoft patches?
Sysadmins, you're either fighting fires or seen as incompetents now
Microsoft: Azure isn't ready for biz-critical apps … yet
Microsoft will move its own IT to the cloud to avoid $200m server bill
Oracle reveals 32-core, 10 BEEELLION-transistor SPARC M7
New chip scales to 1024 cores, 8192 threads 64 TB RAM, at speeds over 3.6GHz
Docker kicks KVM's butt in IBM tests
Big Blue finds containers are speedy, but may not have much room to improve
US regulators OK sale of IBM's x86 server biz to Lenovo
Now all that remains is for gov't offices to ban the boxes
Gartner's Special Report: Should you believe the hype?
Enough hot air to carry a balloon to the Moon
Flash could be CHEAPER than SAS DISK? Come off it, NetApp
Stats analysis reckons we'll hit that point in just three years
Dell The Man shrieks: 'We've got a Bitcoin order, we've got a Bitcoin order'
$50k of PowerEdge servers? That'll be 85 coins in digi-dosh
prev story

Whitepapers

5 things you didn’t know about cloud backup
IT departments are embracing cloud backup, but there’s a lot you need to know before choosing a service provider. Learn all the critical things you need to know.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.
Rethinking backup and recovery in the modern data center
Combining intelligence, operational analytics, and automation to enable efficient, data-driven IT organizations using the HP ABR approach.
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.