But for most Android phones, the fix never arrived. For many, it never will.
That is because it is not clear which company — Google, the smartphone maker or the wireless carrier that sells it — bears ultimate responsibility for the costly process of getting security updates to an Android device. Fixes to known security flaws can take many months to reach individual smartphones, if they arrive at all.
The problem, security experts say, has contributed to making the world’s most popular mobile operating system more vulnerable than its rivals to hackers, scam artists and a growing universe of malicious software.
Breaches remain more common on traditional computers than on smartphones, which have been engineered to include security features not found on desktop or laptop machines, experts say.
But outdated software can undermine such protections. If there was a major outbreak of malicious software, the fractured nature of the system for delivering updates could dramatically slow efforts to protect information carried on Android phones — including documents, passwords, contact lists, pictures, videos, location data and credit card numbers.
The risks are particularly serious for businesses and government agencies, whose increasingly popular bring-your-own-device policies have created new potential portals for espionage aimed at secure computer systems.
“You have potentially millions of Androids making their way into the work space, accessing confidential documents,” said Christopher Soghoian, a former Federal Trade Commission technology expert who now works for the American Civil Liberties Union. “It’s like a really dry forest, and it’s just waiting for a match.”
Google engineers designed Android to resist hackers and have continually improved it. The company also has worked to purge malicious software from its app store, Google Play, minimizing the risk from one possible route of infection.
“We’ve built the system from Day One to deal with this kind of world,” said Hiroshi Lockheimer, vice president of Android engineering. “The health of the Android ecosystem is really important to us.”
Yet while each new generation of Android delivers improvements that close off newly discovered avenues of attack, the company has struggled to get updated software to smartphones already in the hands of consumers.
The latest version of Android — the one with the “smishing” fix — is used by just 1.4 percent of the more than 500 million Android devices worldwide, according to data compiled by Google. The company says it also released a security patch that could repair the flaw in earlier versions of Android, but neither Google nor the wireless carriers could say how many current phones received the patch.