Định nghĩa chính thức

Đặc điểm

Dữ liệu MITRE CWE chính thức

buffer underrun — Some prominent vendors and researchers use the term "buffer underrun". "Buffer underflow" is more commonly used, although both terms are also sometimes used to describe a buffer under-read (CWE-127).

Hiện thực hóa: This typically occurs when a pointer or its index is decremented to a position before the buffer, when pointer arithmetic results in a position before the beginning of the valid memory location, or when a negative index is used.

Dữ liệu MITRE CWE chính thức

Tác động	Phạm vi	Diễn giải
Thay đổi bộ nhớ, Từ chối dịch vụ: sập, thoát hoặc khởi động lại	Tính toàn vẹn, Tính sẵn sàng	Out of bounds memory access will very likely result in the corruption of relevant memory, and perhaps instructions, possibly leading to a crash.
Thực thi mã hoặc lệnh trái phép, Thay đổi bộ nhớ, Vượt qua cơ chế bảo vệ, Khác	Tính toàn vẹn, Tính bí mật, Tính sẵn sàng, Kiểm soát truy cập, Khác	If the corrupted memory can be effectively controlled, it may be possible to execute arbitrary code. If the corrupted memory is data rather than instructions, the system will continue to function with improper changes, possibly in violation of an implicit or explicit policy. The consequences would only be limited by how the affected data is used, such as an adjacent memory location that is used to specify whether the user has special privileges.
Vượt qua cơ chế bảo vệ, Khác	Kiểm soát truy cập, Khác	When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Dữ liệu MITRE CWE chính thức

Yêu cầuChoose a language that is not susceptible to these issues.
Hiện thực hóaAll calculated values that are used as index or for pointer arithmetic should be validated to ensure that they are within an expected range.

Dữ liệu MITRE CWE chính thức

Phương pháp	Cách làm	Hiệu quả
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-124, dựa theo mức độ ưu tiên

Nguồn (2)