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CWE-762

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CWE-762

Mismatched Memory Management Routines

Variant
Incomplete

Description

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.

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Common Consequences

Scope

Integrity
Availability
Confidentiality

Impact

Modify Memory, DoS: Crash, Exit, or Restart, Execute Unauthorized Code or Commands

Potential Mitigations

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().

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.

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.

Architecture and Design

Use a language that provides abstractions for memory allocation and deallocation.

Applicable Platforms

Memory-Unsafe
C
C++

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