REPORT: Millions Of Android Users Vulnerable To Security Breaches

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Millions of Android smartphone users are susceptible to security vulnerabilities such as viruses and malware, according to an internal bulletin prepared by the Department of Homeland Security and the FBI.

The July 23 bulletin, obtained by the website Public Intelligence, reveals that Android - as the most widely used mobile OS - continues to be the target of attacks due to "its market share and open source architecture."

"44 percent of Android users are still using version 2.3.3 through 2.3.7 - known as Gingerbread - which were released in 2011 and have a number of security vulnerabilities that were fixed in later versions," the bulletin reads.

Android leads the smartphone market, with roughly 80% global market share. While more popular in the consumer, rather than the public sector, the bulletin warns that software needs to be kept up-to-date as more federal, state, and local authorities use Android.

The bulletin describes some of the threats if the OS isn't updated to the latest, and more secure software. These include viruses that send out text messages without the user's knowledge, and "rootkits," which are able to log user locations and passwords.

The current 4.3 version of Android, known as Jelly Bean, is considered much safer - with a built-in feature that allows users to scan installed apps for signs of malicious or dirty code, according to Phandroid.