CWE-166 缺失特殊元素净化处理不恰当

Improper Handling of Missing Special Element

结构: Simple

Abstraction: Base

状态: Draft

被利用可能性: unkown

基本描述

The software receives input from an upstream component, but it does not handle or incorrectly handles when an expected special element is missing.

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

可能的缓解方案

策略:

Developers should anticipate that special elements will be removed in the input vectors of their software system. Use an appropriate combination of black lists and whitelists to ensure only valid, expected and appropriate input is processed by the system.

MIT-5 Implementation

策略: Input Validation

Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a whitelist of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs (i.e., do not rely on a blacklist). A blacklist is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, blacklists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

MIT-20 Implementation

策略: Input Validation

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 whitelist validation schemes by introducing dangerous inputs after they have been checked.

分析过的案例

标识	说明	链接
CVE-2002-1362	Crash via message type without separator character	https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-1362
CVE-2002-0729	Missing special character (separator) causes crash	https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-0729
CVE-2002-1532	HTTP GET without \r\n\r\n CRLF sequences causes product to wait indefinitely and prevents other users from accessing it	https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-1532

分类映射

映射的分类名	ImNode ID	Fit	Mapped Node Name
PLOVER			Missing Special Element

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