2021年12月16日16:31:05评论259 views字数 12190阅读40分38秒阅读模式

CWE-190 整数溢出或超界折返

Integer Overflow or Wraparound

结构: Simple

Abstraction: Base

状态: Stable

被利用可能性: Medium

基本描述

The software performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control.

扩展描述

An integer overflow or wraparound occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may wrap to become a very small or negative number. While this may be intended behavior in circumstances that rely on wrapping, it can have security consequences if the wrap is unexpected. This is especially the case if the integer overflow can be triggered using user-supplied inputs. This becomes security-critical when the result is used to control looping, make a security decision, or determine the offset or size in behaviors such as memory allocation, copying, concatenation, etc.

适用平台

Language: {'cwe_Class': 'Language-Independent', 'cwe_Prevalence': 'Undetermined'}

常见的影响

范围	影响	注释
Availability	['DoS: Crash, Exit, or Restart', 'DoS: Resource Consumption (CPU)', 'DoS: Resource Consumption (Memory)', 'DoS: Instability']	This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.
Integrity	Modify Memory	If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.
['Confidentiality', 'Availability', 'Access Control']	['Execute Unauthorized Code or Commands', 'Bypass Protection Mechanism']	This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.

检测方法

DM-1 Automated Static Analysis

This weakness can often be detected using automated static analysis tools. Many modern tools use data flow analysis or constraint-based techniques to minimize the number of false positives.

DM-2 Black Box

Sometimes, evidence of this weakness can be detected using dynamic tools and techniques that interact with the software using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The software's operation may slow down, but it should not become unstable, crash, or generate incorrect results.

Without visibility into the code, black box methods may not be able to sufficiently distinguish this weakness from others, requiring follow-up manual methods to diagnose the underlying problem.

DM-7 Manual Analysis

This weakness can be detected using tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session.

Specifically, manual static analysis is useful for evaluating the correctness of allocation calculations. This can be useful for detecting overflow conditions (CWE-190) or similar weaknesses that might have serious security impacts on the program.

These may be more effective than strictly automated techniques. This is especially the case with weaknesses that are related to design and business rules.