CWE-457
Use of Uninitialized Variable
AI Translation Available
The code uses a variable that has not been initialized, leading to unpredictable or unintended results.
Status
draft
Abstraction
variant
Likelihood
high
Affected Platforms
C
C++
Not Language-Specific
Perl
PHP
Extended Description
AI Translation
In some languages such as C and C++, stack variables are not initialized by default. They generally contain junk data with the contents of stack memory before the function was invoked. An attacker can sometimes control or read these contents. In other languages or conditions, a variable that is not explicitly initialized can be given a default value that has security implications, depending on the logic of the program. The presence of an uninitialized variable can sometimes indicate a typographic error in the code.
Technical Details
AI Translation
Common Consequences
availability
integrity
other
authorization
Impacts
other
Detection Methods
fuzzing
automated static analysis
Potential Mitigations
Phases:
implementation
build and compilation
operation
requirements
architecture and design
Descriptions:
•
Most compilers will complain about the use of uninitialized variables if warnings are turned on.
•
Choose a language that is not susceptible to these issues.
•
Ensure that critical variables are initialized before first use [REF-1485].
•
When using a language that does not require explicit declaration of variables, run or compile the software in a mode that reports undeclared or unknown variables. This may indicate the presence of a typographic error in the variable's name.
•
Mitigating technologies such as safe string libraries and container abstractions could be introduced.