CWE-627: Dynamic Variable Evaluation
CWE版本: 4.18
更新日期: 2025-09-09
弱点描述
In a language where the user can influence the name of a variable at runtime, if the variable names are not controlled, an attacker can read or write to arbitrary variables, or access arbitrary functions.
扩展描述
The resultant vulnerabilities depend on the behavior of the application, both at the crossover point and in any control/data flow that is reachable by the related variables or functions.
常见后果
影响范围: Confidentiality Integrity Availability
技术影响: Modify Application Data Execute Unauthorized Code or Commands
说明: An attacker could gain unauthorized access to internal program variables and execute arbitrary code.
潜在缓解措施
阶段: Implementation
策略: Refactoring
描述: Refactor the code to avoid dynamic variable evaluation whenever possible.
阶段: Implementation
策略: Input Validation
描述: Use only allowlists of acceptable variable or function names.
阶段: Implementation
描述: For function names, ensure that you are only calling functions that accept the proper number of arguments, to avoid unexpected null arguments.
观察示例
参考: CVE-2009-0422
Chain: Dynamic variable evaluation allows resultant remote file inclusion and path traversal.
参考: CVE-2007-2431
Chain: dynamic variable evaluation in PHP program used to modify critical, unexpected $_SERVER variable for resultant XSS.
参考: CVE-2006-4904
Chain: dynamic variable evaluation in PHP program used to conduct remote file inclusion.
参考: CVE-2006-4019
Dynamic variable evaluation in mail program allows reading and modifying attachments and preferences of other users.
引入模式
| 阶段 | 说明 |
|---|---|
| Implementation | - |