CWE-173 候选编码方案处理不恰当
Improper Handling of Alternate Encoding
结构: Simple
Abstraction: Variant
状态: Draft
被利用可能性: unkown
基本描述
The software does not properly handle when an input uses an alternate encoding that is valid for the control sphere to which the input is being sent.
相关缺陷
-
cwe_Nature: ChildOf cwe_CWE_ID: 172 cwe_View_ID: 1000 cwe_Ordinal: Primary
-
cwe_Nature: ChildOf cwe_CWE_ID: 172 cwe_View_ID: 699 cwe_Ordinal: Primary
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cwe_Nature: CanPrecede cwe_CWE_ID: 289 cwe_View_ID: 1000
适用平台
Language: {'cwe_Class': 'Language-Independent', 'cwe_Prevalence': 'Undetermined'}
常见的影响
| 范围 | 影响 | 注释 |
|---|---|---|
| Access Control | Bypass Protection Mechanism |
可能的缓解方案
MIT-44 Architecture and Design
策略: Input Validation
Avoid making decisions based on names of resources (e.g. files) if those resources can have alternate names.
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-30 Implementation
策略: Output Encoding
Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8. When an encoding is not specified, a downstream component may choose a different encoding, either by assuming a default encoding or automatically inferring which encoding is being used, which can be erroneous. When the encodings are inconsistent, the downstream component might treat some character or byte sequences as special, even if they are not special in the original encoding. Attackers might then be able to exploit this discrepancy and conduct injection attacks; they even might be able to bypass protection mechanisms that assume the original encoding is also being used by the downstream component.
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.
分类映射
| 映射的分类名 | ImNode ID | Fit | Mapped Node Name |
|---|---|---|---|
| PLOVER | Alternate Encoding |
相关攻击模式
- CAPEC-120
- CAPEC-267
- CAPEC-3
- CAPEC-4
- CAPEC-52
- CAPEC-53
- CAPEC-64
- CAPEC-71
- CAPEC-72
- CAPEC-78
- CAPEC-79
- CAPEC-80