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Dữ liệu MITRE CWE chính thức

Dữ liệu MITRE CWE chính thức

Tác động	Phạm vi	Diễn giải
Thay đổi bộ nhớ, Thực thi mã hoặc lệnh trái phép	Tính toàn vẹn, Tính bí mật, Tính sẵn sàng	When a program calls free() twice with the same argument, the program's memory management data structures may become corrupted, potentially leading to the reading or modification of unexpected memory addresses. This corruption can cause the program to crash or, in some circumstances, cause two later calls to malloc() to return the same pointer. If malloc() returns the same value twice and the program later gives the attacker control over the data that is written into this doubly-allocated memory, the program becomes vulnerable to a buffer overflow attack. Doubly freeing memory may result in a write-what-where condition, allowing an attacker to execute arbitrary code.

Dữ liệu MITRE CWE chính thức

Kiến trúc và thiết kếChoose a language that provides automatic memory management.
Hiện thực hóaEnsure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
Hiện thực hóaUse a static analysis tool to find double free instances.

Dữ liệu MITRE CWE chính thức

Phương pháp	Cách làm	Hiệu quả
Kiểm thử 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.	Cao
Phân tích tĩnh tự động	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.)	Cao
Phân tích động tự động	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].Crafted inputs are necessary to reach the code containing the error, such as generated by fuzzers. Also, these tools may reduce performance, and they only report the error condition - not the original mistake that led to the error.	Khá

Dữ liệu MITRE CWE chính thức

Dưới đây là các lỗ hổng tiêu biểu liên quan đến CWE-415, dựa theo mức độ ưu tiên

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