How to determine the Security Patch Level of an Android device?

Question

How can I determine the security patch level of an Android device using an API or other mechanism? I'm looking for the same security patch information that can be found manually by clicking the Settings -> About menu on the device.

Google issues security patches every month, for example 2016-12-01.

Answer 1

I do not think that is possible without root access since the Security Patch Level is stored in ro.build.version.security_patch field inside build.prop which is in /system/ path.

If you have root access, you can just read that file and look for the above mentioned field.

EDIT: as @v6ak mentioned, you access the value of the properly without root too.

Answer 2

In Android SDK 23 (Marshmallow) and later, you can retrieve the security patch date from android.os.Build.VERSION.SECURITY_PATCH. The date is a string value in YYYY-MM-DD form.

In Lollipop, you can use the getprop command to read the value of ro.build.version.security_patch. See this S/O question for how to execute getprop using ProcessBuilder.

Security patches have been released on a monthly basis since October 2015, see Android Security Bulletins for more details.

Answer 3

From an adb shell you can execute getprop ro.build.version.security_patch. Hopefully those properties are available to a non-root process on Android.

So in C/C++ I'd try using: system("getprop ro.build.version.security_patch");

Or in Java something like:

import android.os.Bundle;
public static final String SECURITY_PATCH = SystemProperties.get(
            "ro.build.version.security_patch");

Answer 4

This value is stored in the /system/bin/getprop system file. You can read it in this way:

try {
    Process process = new ProcessBuilder()
            .command("/system/bin/getprop")
            .redirectErrorStream(true)
            .start();

    InputStream is = process.getInputStream();
    BufferedReader br = new BufferedReader(new InputStreamReader(is));
    String line;

    while ((line = br.readLine()) != null) {
        str += line + "\n";
        if (str.contains("security_patch")) {
            String[] splitted = line.split(":");
            if (splitted.length == 2) {
                return splitted[1];
            }
            break;
        }
    }

    br.close();
    process.destroy();

} catch (IOException e) {
    e.printStackTrace();
}