This weakness in Android's Java Cryptography Architecture is the root cause of a Bitcoin transaction that reportedly was exploited to pilfer about $5,720 worth of bitcoins out of a digital wallet last week. The disclosure, included in a blog post published Wednesday by Google security engineer Alex Klyubin, was the first official confirmation of the Android vulnerability since Ars and others reported the incident last weekend. Klyubin warned that other apps might also be compromised unless developers change the way they access so-called PRNGs, short for pseudo random number generators.
"We have now determined that applications which use the Java Cryptography Architecture (JCA) for key generation, signing, or random number generation may not receive cryptographically strong values on Android devices due to improper initialization of the underlying PRNG," he wrote. "Applications that directly invoke the system-provided OpenSSL PRNG without explicit initialization on Android are also affected." Apps that establish encrypted connections using the HttpClient and java.net classes aren't vulnerable.
Android flaw used in Bitcoin heist
Posted on Thursday, Aug 15 2013 @ 11:42 CEST by Thomas De Maesschalck