CWE-311 敏感数据加密缺失

Missing Encryption of Sensitive Data

结构: Simple

Abstraction: Class

状态: Draft

被利用可能性: High

基本描述

The software does not encrypt sensitive or critical information before storage or transmission.

扩展描述

The lack of proper data encryption passes up the guarantees of confidentiality, integrity, and accountability that properly implemented encryption conveys.

相关缺陷

• cwe_Nature: ChildOf cwe_CWE_ID: 693 cwe_View_ID: 1000 cwe_Ordinal: Primary

适用平台

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

常见的影响

检测方法

Manual Analysis

Automated Analysis

Manual Static Analysis - Binary or Bytecode

Dynamic Analysis with Automated Results Interpretation

Dynamic Analysis with Manual Results Interpretation

Manual Static Analysis - Source Code

Automated Static Analysis - Source Code

Architecture or Design Review

可能的缓解方案

Requirements

策略:

Clearly specify which data or resources are valuable enough that they should be protected by encryption. Require that any transmission or storage of this data/resource should use well-vetted encryption algorithms.

Architecture and Design

策略:

Ensure that encryption is properly integrated into the system design, including but not necessarily limited to: Identify the separate needs and contexts for encryption: Using threat modeling or other techniques, assume that data can be compromised through a separate vulnerability or weakness, and determine where encryption will be most effective. Ensure that data that should be private is not being inadvertently exposed using weaknesses such as insecure permissions (CWE-732). [REF-7]

MIT-24 Architecture and Design

策略: Libraries or Frameworks

When there is a need to store or transmit sensitive data, use strong, up-to-date cryptographic algorithms to encrypt that data. Select a well-vetted algorithm that is currently considered to be strong by experts in the field, and use well-tested implementations. As with all cryptographic mechanisms, the source code should be available for analysis. For example, US government systems require FIPS 140-2 certification. Do not develop custom or private cryptographic algorithms. They will likely be exposed to attacks that are well-understood by cryptographers. Reverse engineering techniques are mature. If the algorithm can be compromised if attackers find out how it works, then it is especially weak. Periodically ensure that the cryptography has not become obsolete. Some older algorithms, once thought to require a billion years of computing time, can now be broken in days or hours. This includes MD4, MD5, SHA1, DES, and other algorithms that were once regarded as strong. [REF-267]

MIT-46 Architecture and Design

策略: Separation of Privilege

Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design and that the compartmentalization serves to allow for and further reinforce privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide when it is appropriate to use and to drop system privileges.

MIT-25 ['Implementation', 'Architecture and Design']

策略:

When using industry-approved techniques, use them correctly. Don't cut corners by skipping resource-intensive steps (CWE-325). These steps are often essential for preventing common attacks.

MIT-33 Implementation

策略: Attack Surface Reduction

Use naming conventions and strong types to make it easier to spot when sensitive data is being used. When creating structures, objects, or other complex entities, separate the sensitive and non-sensitive data as much as possible.

示例代码

例

This code writes a user's login information to a cookie so the user does not have to login again later.

bad PHP

The code stores the user's username and password in plaintext in a cookie on the user's machine. This exposes the user's login information if their computer is compromised by an attacker. Even if the user's machine is not compromised, this weakness combined with cross-site scripting (CWE-79) could allow an attacker to remotely copy the cookie.

Also note this example code also exhibits Plaintext Storage in a Cookie (CWE-315).

例

The following code attempts to establish a connection, read in a password, then store it to a buffer.

bad C

While successful, the program does not encrypt the data before writing it to a buffer, possibly exposing it to unauthorized actors.

例

The following code attempts to establish a connection to a site to communicate sensitive information.

bad Java

Though a connection is successfully made, the connection is unencrypted and it is possible that all sensitive data sent to or received from the server will be read by unintended actors.

分析过的案例

Notes

分类映射

相关攻击模式

• CAPEC-157
• CAPEC-158
• CAPEC-204
• CAPEC-31
• CAPEC-37
• CAPEC-383
• CAPEC-384
• CAPEC-385
• CAPEC-386
• CAPEC-387
• CAPEC-388
• CAPEC-477
• CAPEC-609
• CAPEC-65

引用

• REF-7 Writing Secure Code

• REF-44 24 Deadly Sins of Software Security

• REF-265 Top 25 Series - Rank 10 - Missing Encryption of Sensitive Data

• REF-62 The Art of Software Security Assessment

• REF-267 SECURITY REQUIREMENTS FOR CRYPTOGRAPHIC MODULES