Return of Stack Variable Address
Weakness ID: 562 (Weakness Base)Status: Draft
+ Description

Description Summary

A function returns the address of a stack variable, which will cause unintended program behavior, typically in the form of a crash.
+ Time of Introduction
  • Implementation
+ Applicable Platforms

Languages

C

C++

+ Demonstrative Examples

Example 1

The following function returns a stack address.

(Bad Code)
Example Language:
char* getName() {
char name[STR_MAX];
fillInName(name);
return name;
}
+ Potential Mitigations

Use static analysis tools to spot return of the address of a stack variable.

+ Other Notes

Because local variables are allocated on the stack, when a program returns a pointer to a local variable, it is returning a stack address. A subsequent function call is likely to re-use this same stack address, thereby overwriting the value of the pointer, which no longer corresponds to the same variable since a function's stack frame is invalidated when it returns. At best this will cause the value of the pointer to change unexpectedly. In many cases it causes the program to crash the next time the pointer is dereferenced. The problem can be hard to debug because the cause of the problem is often far removed from the symptom.

+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness ClassWeakness Class398Indicator of Poor Code Quality
Development Concepts (primary)699
Research Concepts1000
ChildOfWeakness BaseWeakness Base672Operation on a Resource after Expiration or Release
Research Concepts (primary)1000
ChildOfCategoryCategory748CERT C Secure Coding Section 50 - POSIX (POS)
Weaknesses Addressed by the CERT C Secure Coding Standard (primary)734
+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
Anonymous Tool Vendor (under NDA)
CERT C Secure CodingPOS34-CDo not call putenv() with a pointer to an automatic variable as the argument
+ Content History
Submissions
Submission DateSubmitterOrganizationSource
Anonymous Tool Vendor (under NDA)Externally Mined
Modifications
Modification DateModifierOrganizationSource
2008-07-01Eric DalciCigitalExternal
updated Potential Mitigations, Time of Introduction
2008-09-08CWE Content TeamMITREInternal
updated Applicable Platforms, Relationships, Other Notes, Taxonomy Mappings
2008-11-24CWE Content TeamMITREInternal
updated Relationships, Taxonomy Mappings
2009-05-27CWE Content TeamMITREInternal
updated Demonstrative Examples
Previous Entry Names
Change DatePrevious Entry Name
2008-04-11Stack Address Returned