CWE-909 – Missing Initialization of Resource

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Description

The software does not initialize a critical resource.

Many resources require initialization before they can be properly used. If a resource is not initialized, it could contain unpredictable or expired data, or it could be initialized to defaults that are invalid. This can have security implications when the resource is expected to have certain properties or values.

Modes of Introduction:

– Implementation

Likelihood of Exploit: Medium

 

Related Weaknesses

CWE-665
CWE-665
CWE-908

 

Consequences

Confidentiality: Read Memory, Read Application Data

When reusing a resource such as memory or a program variable, the original contents of that resource may not be cleared before it is sent to an untrusted party.

Availability: DoS: Crash, Exit, or Restart

The uninitialized resource may contain values that cause program flow to change in ways that the programmer did not intend.

 

Potential Mitigations

Phase: Implementation

Effectiveness:

Description: 

Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all specified steps.

Phase: Implementation

Effectiveness:

Description: 

Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.

Phase: Implementation

Effectiveness:

Description: 

Avoid race conditions (CWE-362) during initialization routines.

Phase: Build and Compilation

Effectiveness:

Description: 

Run or compile your software with settings that generate warnings about uninitialized variables or data.

CVE References

 

  • CVE-2020-20739
    • A variable that has its value set in a conditional statement is sometimes used when the conditional fails, sometimes causing data leakage
  • CVE-2005-1036
    • Chain: Bypass of access restrictions due to improper authorization (CWE-862) of a user results from an improperly initialized (CWE-909) I/O permission bitmap