CWE-590 詳細

The product calls free() on a pointer to memory that was not allocated using associated heap allocation functions such as malloc(), calloc(), or realloc().

導入モード

Implementation

適用可能なプラットフォーム

言語

クラス： Memory-Unsafe (Undetermined)
名前： C (Undetermined)

一般的な結果

観察された例

潜在的な緩和策

Phases : Implementation
Only free pointers that you have called malloc on previously. This is the recommended solution. Keep track of which pointers point at the beginning of valid chunks and free them only once.
Phases : Implementation
Before freeing a pointer, the programmer should make sure that the pointer was previously allocated on the heap and that the memory belongs to the programmer. Freeing an unallocated pointer will cause undefined behavior in the program.
Phases : Architecture and Design
Phases : Architecture and Design
Use a language that provides abstractions for memory allocation and deallocation.

検出方法

Fuzzing

Fuzz testing (fuzzing) is a powerful technique for generating large numbers of diverse inputs - either randomly or algorithmically - and dynamically invoking the code with those inputs. Even with random inputs, it is often capable of generating unexpected results such as crashes, memory corruption, or resource consumption. Fuzzing effectively produces repeatable test cases that clearly indicate bugs, which helps developers to diagnose the issues.
有効性 : High

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
有効性 : High

Automated Dynamic Analysis

Use tools that are integrated during compilation to insert runtime error-checking mechanisms related to memory safety errors, such as AddressSanitizer (ASan) for C/C++ [REF-1518] or valgrind [REF-480].
有効性 : Moderate

脆弱性マッピングノート

理由 : 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.
コメント : 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.

ノート

In C++, if the new operator was used to allocate the memory, it may be allocated with the malloc(), calloc() or realloc() family of functions in the implementation. Someone aware of this behavior might choose to map this problem to CWE-590 or to its parent, CWE-762, depending on their perspective.

参考文献

REF-480

Valgrind
https://valgrind.org/

REF-1518

AddressSanitizer
https://clang.llvm.org/docs/AddressSanitizer.html

登録情報

変更履歴