界: Input Validation and Representation

输入验证与表示问题是由元字符、交替编码和数字表示引起的。安全问题源于信任输入。这些问题包括：“Buffer Overflows”、“Cross-Site Scripting”攻击、“SQL Injection”等其他问题。

Server-Side Template Injection

Abstract

用户控制的数据用作模板引擎的模板，使得攻击者能够访问模板上下文，并在某些情况下在应用程序服务器中注入和运行任意代码。

Explanation

模板引擎用于使用动态数据呈现内容。此上下文数据通常由用户控制并通过模板设置格式，以生成 Web 页面、电子邮件等。模板引擎可通过条件、循环等代码构造处理上下文数据，从而允许在模板中使用功能强大的语言表达式来呈现动态内容。如果攻击者能够控制要呈现的模板，他们将能够通过注入表达式来公开上下文数据，甚至在服务器上运行任意命令。

示例 1：下面的示例显示了如何通过 HTTP 请求检索模板并呈现该模板。


// Set up the context data
VelocityContext context = new VelocityContext();
context.put( "name", user.name );

// Load the template
String template = getUserTemplateFromRequestBody(request);
RuntimeServices runtimeServices = RuntimeSingleton.getRuntimeServices();
StringReader reader = new StringReader(template);
SimpleNode node = runtimeServices.parse(reader, "myTemplate");
template = new Template();
template.setRuntimeServices(runtimeServices);
template.setData(node);
template.initDocument();

// Render the template with the context data
StringWriter sw = new StringWriter();
template.merge( context, sw );

Example 1 使用 Velocity 作为模板引擎。对于该引擎，攻击者可以提交以下模板以在服务器上运行任意命令：


$name.getClass().forName("java.lang.Runtime").getRuntime().exec(<COMMAND>)

References

[1] Server-Side Template Injection: RCE for the modern webapp

[2] Standards Mapping - Common Weakness Enumeration CWE ID 95

[3] Standards Mapping - Common Weakness Enumeration Top 25 2019 [18] CWE ID 094

[4] Standards Mapping - Common Weakness Enumeration Top 25 2020 [17] CWE ID 094

[5] Standards Mapping - Common Weakness Enumeration Top 25 2022 [25] CWE ID 094

[6] Standards Mapping - Common Weakness Enumeration Top 25 2023 [23] CWE ID 094

[7] Standards Mapping - Common Weakness Enumeration Top 25 2024 [11] CWE ID 094

[8] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-002754

[9] Standards Mapping - FIPS200 SI

[10] Standards Mapping - General Data Protection Regulation (GDPR) Indirect Access to Sensitive Data

[11] Standards Mapping - NIST Special Publication 800-53 Revision 4 SI-10 Information Input Validation (P1)

[12] Standards Mapping - NIST Special Publication 800-53 Revision 5 SI-10 Information Input Validation

[13] Standards Mapping - OWASP Application Security Verification Standard 4.0 5.2.4 Sanitization and Sandboxing Requirements (L1 L2 L3), 5.2.5 Sanitization and Sandboxing Requirements (L1 L2 L3), 5.2.8 Sanitization and Sandboxing Requirements (L1 L2 L3), 5.3.6 Output Encoding and Injection Prevention Requirements (L1 L2 L3)

[14] Standards Mapping - OWASP Mobile 2014 M1 Weak Server Side Controls

[15] Standards Mapping - OWASP Mobile 2024 M4 Insufficient Input/Output Validation

[16] Standards Mapping - OWASP Top 10 2004 A6 Injection Flaws

[17] Standards Mapping - OWASP Top 10 2007 A2 Injection Flaws

[18] Standards Mapping - OWASP Top 10 2010 A1 Injection

[19] Standards Mapping - OWASP Top 10 2013 A1 Injection

[20] Standards Mapping - OWASP Top 10 2017 A1 Injection

[21] Standards Mapping - OWASP Top 10 2021 A03 Injection

[22] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 6.5.6

[23] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 6.3.1.1, Requirement 6.5.2

[24] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 Requirement 6.5.1

[25] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.1

[26] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.1

[27] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.1

[28] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.1

[29] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 6.2.4

[30] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0.1 Requirement 6.2.4

[31] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 4.2 - Critical Asset Protection

[32] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.1 - Terminal Software Attack Mitigation, Control Objective B.3.1.1 - Terminal Software Attack Mitigation

[33] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.1 - Terminal Software Attack Mitigation, Control Objective B.3.1.1 - Terminal Software Attack Mitigation, Control Objective C.3.2 - Web Software Attack Mitigation

[34] Standards Mapping - SANS Top 25 2009 Insecure Interaction - CWE ID 116

[35] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3510 CAT I, APP3570 CAT I

[36] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3510 CAT I, APP3570 CAT I

[37] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3510 CAT I, APP3570 CAT I

[38] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3510 CAT I, APP3570 CAT I

[39] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3510 CAT I, APP3570 CAT I

[40] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3510 CAT I, APP3570 CAT I

[41] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3510 CAT I, APP3570 CAT I

[42] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002560 CAT I

[43] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002560 CAT I

[44] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002560 CAT I

[45] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002560 CAT I

[46] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002560 CAT I

[47] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002560 CAT I

[48] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002560 CAT I

[49] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002560 CAT I

[50] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002560 CAT I

[51] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002560 CAT I

[52] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002560 CAT I

[53] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002560 CAT I

[54] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002560 CAT I

[55] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002530 CAT II, APSC-DV-002560 CAT I

[56] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002530 CAT II, APSC-DV-002560 CAT I

[57] Standards Mapping - Web Application Security Consortium Version 2.00 Improper Input Handling (WASC-20)

desc.dataflow.java.server_side_template_injection

Abstract

用户控制的数据用作模板引擎的模板，这使得攻击者能够访问模板上下文，并在某些情况下在应用程序服务器中注入和运行任意代码。

Explanation


app.get('/', function(req, res){
    var template = _.template(req.params['template']);
    res.write("<html><body><h2>Hello World!</h2>" + template() + "</body></html>");
});

Example 1 会使用 Underscore.js 作为 Node.js 应用程序中的模板引擎。对于该引擎，攻击者可以提交以下模板以在服务器上运行任意命令：


<% cp = process.mainModule.require('child_process');cp.exec(<COMMAND>); %>