CWE-585: Empty Synchronized Block

Description

The product contains an empty synchronized block.

Submission Date :

Dec. 15, 2006, midnight

Modification Date :

2023-06-29 00:00:00+00:00

Organization :

MITRE
Extended Description

An empty synchronized block does not actually accomplish any synchronization and may indicate a troubled section of code. An empty synchronized block can occur because code no longer needed within the synchronized block is commented out without removing the synchronized block.

Example Vulnerable Codes

Example - 1

The following code attempts to synchronize on an object, but does not execute anything in the synchronized block. This does not actually accomplish anything and may be a sign that a programmer is wrestling with synchronization but has not yet achieved the result they intend.

synchronized(this) { }

Instead, in a correct usage, the synchronized statement should contain procedures that access or modify data that is exposed to multiple threads. For example, consider a scenario in which several threads are accessing student records at the same time. The method which sets the student ID to a new value will need to make sure that nobody else is accessing this data at the same time and will require synchronization.

this.ID = ID;synchronized(this){}public void setID(int ID){}

Related Weaknesses

This table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined to give an overview of the different insight to similar items that may exist at higher and lower levels of abstraction.

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