CWE-665: Improper Initialization

MITRE CWE weakness

Description

The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used.

This can have security implications when the associated resource is expected to have certain properties or values, such as a variable that determines whether a user has been authenticated or not.

Common consequences

• Confidentiality: Read Memory, Read Application Data
• Access Control: Bypass Protection Mechanism
• Availability: DoS: Crash, Exit, or Restart

Mitigations

Requirements — Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, in Java, if the programmer does not explicitly initialize a variable, then the code could produce a compile-time error (if the variable is local) or automatically initialize the variable to the default value for the variable's type. In Perl, if explicit initialization is not performed, then a default value of undef is assigned, which is interpreted as 0, false, or an equivalent value depending on the context in which the variable is accessed.

Architecture and Design — Identify all variables and data stores that receive information from external sources, and apply input validation to make sure that they are only initialized to expected values.

Implementation — Explicitly initialize all your variables and other data stores, either during declaration or just before the first usage.

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

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

References

• CWE page: https://cwe.mitre.org/data/definitions/665.html
• CWE list: https://cwe.mitre.org/data/index.html