 
                            ...
When sendBroadcast() is used, normally any other application, including a malicious application, can receive the broadcast.
This facilitates intent sniffing, see [viaForensics 2014] 26. Android: avoid intent sniffing.
Therefore, receivers of broadcast intents should be restricted.  One way to restrict receivers is to use an explicit intent. An explicit intent can specify a component (using setComponent(ComponentName)) or a class (using setClass(Context, Class)) so that only the specified component or class can resolve the intent.
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| [Chin 2011] | Analyzing Inter-Application Communication in Android | 
| 4.2.2.5. When sending sensitive information with a broadcast, limit the receivable receiver | |
| [viaForensics 2014] | 26. Android: avoid intent sniffing | 
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