CWE-762 Detail

The product attempts to return a memory resource to the system, but it calls a release function that is not compatible with the function that was originally used to allocate that resource.

This weakness can be generally described as mismatching memory management routines, such as:

• The memory was allocated on the stack (automatically), but it was deallocated using the memory management routine free() (CWE-590), which is intended for explicitly allocated heap memory.
• The memory was allocated explicitly using one set of memory management functions, and deallocated using a different set. For example, memory might be allocated with malloc() in C++ instead of the new operator, and then deallocated with the delete operator.

When the memory management functions are mismatched, the consequences may be as severe as code execution, memory corruption, or program crash. Consequences and ease of exploit will vary depending on the implementation of the routines and the object being managed.

Modes Of Introduction

Implementation

Applicable Platforms

Language

Name: C (Undetermined)
Name: C++ (Undetermined)

Common Consequences

Potential Mitigations

Phases : Implementation
Only call matching memory management functions. Do not mix and match routines. For example, when you allocate a buffer with malloc(), dispose of the original pointer with free().
Phases : Implementation

Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.

For example, glibc in Linux provides protection against free of invalid pointers.

When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].

To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

Phases : Architecture and Design

Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

For example, glibc in Linux provides protection against free of invalid pointers.

Phases : Architecture and Design
Use a language that provides abstractions for memory allocation and deallocation.
Phases : Testing
Use a tool that dynamically detects memory management problems, such as valgrind.

Vulnerability Mapping Notes

Justification : This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Comment : Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

NotesNotes

This weakness is possible in any programming language that allows manual management of memory.

References

REF-657

boost C++ Library Smart Pointers
https://www.boost.org/doc/libs/1_38_0/libs/smart_ptr/smart_ptr.htm

REF-480

Valgrind
http://valgrind.org/

REF-391

Transitioning to ARC Release Notes
iOS Developer Library.
https://developer.apple.com/library/archive/releasenotes/ObjectiveC/RN-TransitioningToARC/Introduction/Introduction.html

Submission

Modifications