SAN FRANCISCO — Millions of smartphones and tablets running Google’s Android operating system have the Heartbleed software bug, in a sign of how broadly the flaw extends beyond the Internet and into consumer devices.

While Google said in a blog post on April 9 that all versions of Android are immune to the flaw, it added that the “limited exception” was one version dubbed 4.1.1, which was released in 2012.

Security researchers said that version of Android is still used in millions of smartphones and tablets, including popular models made by Samsung, HTC and other manufacturers. Google statistics show that 34 percent of Android devices use variations of the 4.1 software. The company said less than 10 percent of active devices are vulnerable. More than 900 million Android devices have been activated worldwide.

The Heartbleed vulnerability, made public earlier this week, can expose people to hacking of their passwords and other sensitive information. While a fix was simultaneously made available and quickly implemented by the majority of Internet properties that were vulnerable to the bug, there is no easy solution for Android gadgets that carry the flaw, security experts said. Even though Google has provided a patch, the company said it is up to handset makers and wireless carriers to update the devices — and for Android, “the update cycle is really long,” said Michael Shaulov, chief executive officer and co-founder of Lacoon Security, a cyber-security company focused on advanced mobile threats.