CWE-152 宏符号转义处理不恰当

Improper Neutralization of Macro Symbols

结构: Simple

Abstraction: Variant

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 neutralize or incorrectly neutralizes special elements that could be interpreted as macro symbols when they are sent to a downstream component.

相关缺陷

• cwe_Nature: ChildOf cwe_CWE_ID: 138 cwe_View_ID: 1000 cwe_Ordinal: Primary

• cwe_Nature: ChildOf cwe_CWE_ID: 138 cwe_View_ID: 699 cwe_Ordinal: Primary

适用平台

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

常见的影响

范围	影响	注释
Integrity	Unexpected State

可能的缓解方案

Implementation

策略: Input Validation

Developers should anticipate that macro symbols will be injected/removed/manipulated 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-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.

分析过的案例

标识	说明	链接
CVE-2002-0770	Server trusts client to expand macros, allows macro characters to be expanded to trigger resultant information exposure.	https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-0770
CVE-2008-2018	Attacker can obtain sensitive information from a database by using a comment containing a macro, which inserts the data during expansion.	https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2018

Notes

分类映射

映射的分类名	ImNode ID	Fit	Mapped Node Name
PLOVER			Macro Symbol
Software Fault Patterns	SFP24		Tainted input to command