CWE-179: Incorrect Behavior Order: Early Validation
CWE版本: 4.18
更新日期: 2025-09-09
弱点描述
The product validates input before applying protection mechanisms that modify the input, which could allow an attacker to bypass the validation via dangerous inputs that only arise after the modification.
扩展描述
Product needs to validate data at the proper time, after data has been canonicalized and cleansed. Early validation is susceptible to various manipulations that result in dangerous inputs that are produced by canonicalization and cleansing.
常见后果
影响范围: Access Control Integrity
技术影响: Bypass Protection Mechanism Execute Unauthorized Code or Commands
说明: An attacker could include dangerous input that bypasses validation protection mechanisms which can be used to launch various attacks including injection attacks, execute arbitrary code or cause other unintended behavior.
潜在缓解措施
阶段: Implementation
策略: Input Validation
描述: Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
观察示例
参考: CVE-2002-0433
Product allows remote attackers to view restricted files via an HTTP request containing a "*" (wildcard or asterisk) character.
参考: CVE-2003-0332
Product modifies the first two letters of a filename extension after performing a security check, which allows remote attackers to bypass authentication via a filename with a .ats extension instead of a .hts extension.
参考: CVE-2002-0802
Database consumes an extra character when processing a character that cannot be converted, which could remove an escape character from the query and make the application subject to SQL injection attacks.
参考: CVE-2000-0191
Overlaps "fakechild/../realchild"
参考: CVE-2004-2363
Product checks URI for "<" and other literal characters, but does it before hex decoding the URI, so "%3E" and other sequences are allowed.
参考: CVE-2002-0934
Directory traversal vulnerability allows remote attackers to read or modify arbitrary files via invalid characters between two . (dot) characters, which are filtered and result in a ".." sequence.
参考: CVE-2003-0282
Directory traversal vulnerability allows attackers to overwrite arbitrary files via invalid characters between two . (dot) characters, which are filtered and result in a ".." sequence.
引入模式
| 阶段 | 说明 |
|---|---|
| Implementation | Since early validation errors usually arise from improperly implemented defensive mechanisms, it is likely that these will be introduced more frequently as secure programming becomes implemented more widely. |
适用平台
编程语言
分类映射
| 分类名称 | 条目ID | 条目名称 | 映射适配度 |
|---|---|---|---|
| PLOVER | - | Early Validation Errors | - |
关键信息
CWE ID: CWE-179
抽象级别: Base
结构: Simple
状态: Incomplete