CWE-306 关键功能的认证机制缺失

Missing Authentication for Critical Function

结构: Simple

Abstraction: Base

状态: Draft

被利用可能性: High

基本描述

The software does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

相关缺陷

  • cwe_Nature: ChildOf cwe_CWE_ID: 287 cwe_View_ID: 1000 cwe_Ordinal: Primary

  • cwe_Nature: ChildOf cwe_CWE_ID: 287 cwe_View_ID: 1003 cwe_Ordinal: Primary

  • cwe_Nature: ChildOf cwe_CWE_ID: 287 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
['Access Control', 'Other'] ['Gain Privileges or Assume Identity', 'Other'] Exposing critical functionality essentially provides an attacker with the privilege level of that functionality. The consequences will depend on the associated functionality, but they can range from reading or modifying sensitive data, access to administrative or other privileged functionality, or possibly even execution of arbitrary code.

检测方法

DM-7.2 Manual Analysis

This weakness can be detected using tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session.

Specifically, manual static analysis is useful for evaluating the correctness of custom authentication mechanisms.

These may be more effective than strictly automated techniques. This is especially the case with weaknesses that are related to design and business rules.

DM-6.1 Automated Static Analysis

Automated static analysis is useful for detecting commonly-used idioms for authentication. A tool may be able to analyze related configuration files, such as .htaccess in Apache web servers, or detect the usage of commonly-used authentication libraries.

Generally, automated static analysis tools have difficulty detecting custom authentication schemes. In addition, the software's design may include some functionality that is accessible to any user and does not require an established identity; an automated technique that detects the absence of authentication may report false positives.

Manual Static Analysis - Binary or Bytecode

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:
  • Binary / Bytecode disassembler - then use manual analysis for vulnerabilities & anomalies

Dynamic Analysis with Automated Results Interpretation

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:
  • Web Application Scanner
  • Web Services Scanner
  • Database Scanners

Dynamic Analysis with Manual Results Interpretation

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:
  • Host Application Interface Scanner
  • Fuzz Tester
  • Framework-based Fuzzer

Manual Static Analysis - Source Code

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:
  • Focused Manual Spotcheck - Focused manual analysis of source
  • Manual Source Code Review (not inspections)

Automated Static Analysis - Source Code

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:
  • Source code Weakness Analyzer
  • Context-configured Source Code Weakness Analyzer

Architecture or Design Review

According to SOAR, the following detection techniques may be useful:

Highly cost effective:
  • Inspection (IEEE 1028 standard) (can apply to requirements, design, source code, etc.)
  • Formal Methods / Correct-By-Construction
Cost effective for partial coverage:
  • Attack Modeling

可能的缓解方案

Architecture and Design

策略:

Divide the software into anonymous, normal, privileged, and administrative areas. Identify which of these areas require a proven user identity, and use a centralized authentication capability. Identify all potential communication channels, or other means of interaction with the software, to ensure that all channels are appropriately protected. Developers sometimes perform authentication at the primary channel, but open up a secondary channel that is assumed to be private. For example, a login mechanism may be listening on one network port, but after successful authentication, it may open up a second port where it waits for the connection, but avoids authentication because it assumes that only the authenticated party will connect to the port. In general, if the software or protocol allows a single session or user state to persist across multiple connections or channels, authentication and appropriate credential management need to be used throughout.

MIT-15 Architecture and Design

策略:

For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Architecture and Design

策略:

Where possible, avoid implementing custom authentication routines and consider using authentication capabilities as provided by the surrounding framework, operating system, or environment. These may make it easier to provide a clear separation between authentication tasks and authorization tasks. In environments such as the World Wide Web, the line between authentication and authorization is sometimes blurred. If custom authentication routines are required instead of those provided by the server, then these routines must be applied to every single page, since these pages could be requested directly.

MIT-4.5 Architecture and Design

策略: Libraries or Frameworks

Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator [REF-45].

示例代码

例

In the following Java example the method createBankAccount is used to create a BankAccount object for a bank management application.

bad Java

public BankAccount createBankAccount(String accountNumber, String accountType,
String accountName, String accountSSN, double balance) {
BankAccount account = new BankAccount();
account.setAccountNumber(accountNumber);
account.setAccountType(accountType);
account.setAccountOwnerName(accountName);
account.setAccountOwnerSSN(accountSSN);
account.setBalance(balance);

return account;
}

However, there is no authentication mechanism to ensure that the user creating this bank account object has the authority to create new bank accounts. Some authentication mechanisms should be used to verify that the user has the authority to create bank account objects.

The following Java code includes a boolean variable and method for authenticating a user. If the user has not been authenticated then the createBankAccount will not create the bank account object.

good Java

private boolean isUserAuthentic = false;

// authenticate user,

// if user is authenticated then set variable to true

// otherwise set variable to false
public boolean authenticateUser(String username, String password) {
...
}

public BankAccount createNewBankAccount(String accountNumber, String accountType,
String accountName, String accountSSN, double balance) {
BankAccount account = null;

if (isUserAuthentic) {
account = new BankAccount();
account.setAccountNumber(accountNumber);
account.setAccountType(accountType);
account.setAccountOwnerName(accountName);
account.setAccountOwnerSSN(accountSSN);
account.setBalance(balance);
}
return account;
}

分析过的案例

标识 说明 链接
CVE-2002-1810 MFV. Access TFTP server without authentication and obtain configuration file with sensitive plaintext information. https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-1810
CVE-2008-6827 Agent software running at privileges does not authenticate incoming requests over an unprotected channel, allowing a Shatter" attack. https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-6827
CVE-2004-0213 Product enforces restrictions through a GUI but not through privileged APIs. https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2004-0213

Notes

分类映射

映射的分类名 ImNode ID Fit Mapped Node Name
PLOVER No Authentication for Critical Function
Software Fault Patterns SFP31 Missing authentication

相关攻击模式

  • CAPEC-12
  • CAPEC-166
  • CAPEC-36
  • CAPEC-62

引用