界: Encapsulation

封裝是要劃定清楚的界限。在網頁瀏覽器中，這可能意味著確保您的行動程式碼不會被其他行動程式碼濫用。在伺服器上，這可能意味著區分經過驗證的資料與未經驗證的資料、區分一個使用者的資料與另一個使用者的資料，或區分允許使用者查看的資料與不允許查看的資料。

Mass Assignment: Sensitive Field Exposure

C#/VB.NET/ASP.NET
Java/JSP

Abstract

敏感欄位會暴露給模型繫結器。

Explanation

現代的架構允許開發人員同時從要求查詢與主體，將 HTTP 要求參數自動繫結至模型物件，以簡化開發並提高生產力。如果未正確配置繫結器來控制繫結哪些 HTTP 要求參數至哪些模型屬性，則攻擊者可能會濫用模型繫結程序，並設定不應暴露給使用者控制的任何其他屬性。即使模型屬性不會出現在網頁表單或 API 約定中，這種繫結也是可能會發生。

範例 1：以下的 ASP.NET MVC 控制項方法 (Register) 會從網頁表單存取，此表單會要求使用者提供名稱及密碼來註冊帳戶：


public ActionResult Register(RegisterModel model)
{
    if (ModelState.IsValid)
    {
        try
        {
            return RedirectToAction("Index", "Home");
        }
        catch (MembershipCreateUserException e)
        {
            ModelState.AddModelError("", "");
        }
    }
    return View(model);
}

其中 RegisterModel 類別定義為：


public class RegisterModel
{
    [BindRequired]
    [Display(Name = "User name")]
    public string UserName { get; set; }

    [BindRequired]
    [DataType(DataType.Password)]
    [Display(Name = "Password")]
    public string Password { get; set; }

    [DataType(DataType.Password)]
    [Display(Name = "Confirm password")]
    public string ConfirmPassword { get; set; }

    public Details Details { get; set; }

    public RegisterModel()
    {
        Details = new Details();
    }
}

而 Details 類別定義為：


public class Details
{
    public bool IsAdmin { get; set; }
    ...
}

根據 Example 1 中的情況，攻擊者可能會探索應用程式並發現 RegisterModel 模型中有一個 Details 屬性。若是如此，攻擊者接著可能會嘗試覆寫指派給其屬性的目前值。
如果攻擊者能找到這些內部屬性，而架構繫結器未正確配置以禁止繫結這些屬性，則攻擊者將可以傳送以下要求來註冊管理員帳戶：


name=John&password=****&details.is_admin=true

References

[1] OWASP Mass assignment

[2] Standards Mapping - Common Weakness Enumeration CWE ID 915

[3] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-001082, CCI-002754

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

[5] Standards Mapping - NIST Special Publication 800-53 Revision 4 SC-2 Application Partitioning (P1), SI-10 Information Input Validation (P1)

[6] Standards Mapping - NIST Special Publication 800-53 Revision 5 SC-2 Separation of System and User Functionality, SI-10 Information Input Validation

[7] Standards Mapping - OWASP API 2023 API3 Broken Object Property Level Authorization

[8] Standards Mapping - OWASP Application Security Verification Standard 4.0 5.1.2 Input Validation Requirements (L1 L2 L3)

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

[10] Standards Mapping - OWASP Top 10 2004 A1 Unvalidated Input

[11] Standards Mapping - OWASP Top 10 2007 A4 Insecure Direct Object Reference

[12] Standards Mapping - OWASP Top 10 2010 A4 Insecure Direct Object References

[13] Standards Mapping - OWASP Top 10 2013 A4 Insecure Direct Object References

[14] Standards Mapping - OWASP Top 10 2017 A5 Broken Access Control

[15] Standards Mapping - OWASP Top 10 2021 A08 Software and Data Integrity Failures

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

[17] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 6.5.2

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

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

[20] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.8

[21] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.8

[22] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.8

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

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

[25] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 5.4 - Authentication and Access Control

[26] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 5.4 - Authentication and Access Control

[27] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 5.4 - Authentication and Access Control, Control Objective C.2.3 - Web Software Access Controls

[28] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[29] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[30] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[31] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[32] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[33] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[34] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[35] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[36] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[37] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[38] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[39] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[40] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[41] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[42] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[43] Standards Mapping - Web Application Security Consortium Version 2.00 Insufficient Process Validation (WASC-40)

desc.structural.dotnet.mass_assignment_sensitive_field_exposure

Abstract

敏感欄位會暴露給模型繫結器。

Explanation

現代的架構允許開發人員同時從要求查詢與主文，將 HTTP 要求參數自動繫結至模型物件，以簡化開發並提高生產力。如果未正確設定繫結器來控制繫結哪些 HTTP 要求參數至哪些模型屬性，則攻擊者可能會濫用模型繫結程序，並設定不應暴露給使用者控制的任何其他屬性。即使模型屬性不會出現在網頁表單或 API 約定中，這種繫結也是可能會發生。

範例 1：以下 Struts 1 DynaActionForm 動態定義繫結至使用者要求的 ActionForm。此案例中，會透過提供帳戶的類型與使用者詳細資料的方式，將其用於註冊帳戶：


<struts-config>
  <form-beans>
       <form-bean name="dynaUserForm"
          type="org.apache.struts.action.DynaActionForm" >
              <form-property name="type" type="java.lang.String" />
              <form-property name="user" type="com.acme.common.User" />
       </form-bean>
       ...

如果註冊成功，使用者資料就會持續存留在資料庫中。User 類別定義為：


public class User {
  private String name;
  private String lastname;
  private int age;
  private Details details;

  // Public Getters and Setters
  ...
}

而 Details 類別定義為：


public class Details {
  private boolean is_admin;
  private int id;
  private Date login_date;

  // Public Getters and Setters
  ...
}

根據 Example 1 中的情況，攻擊者可能會探索應用程式並發現 User 模型中有一個 details 屬性。若是如此，攻擊者接著可能會嘗試覆寫指派給其屬性的目前值。
如果攻擊者能找到這些內部屬性，而架構繫結器未正確設定以禁止繫結這些屬性，則攻擊者將可以傳送以下要求來註冊管理員帳戶：


type=free&user.name=John&user.lastname=Smith&age=22&details.is_admin=true

References

[1] OWASP Mass assignment

[2] Spring Spring MVC Known Vulnerabilities and Issues

[3] Standards Mapping - Common Weakness Enumeration CWE ID 915

[4] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-001082, CCI-002754

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

[6] Standards Mapping - NIST Special Publication 800-53 Revision 4 SC-2 Application Partitioning (P1), SI-10 Information Input Validation (P1)

[7] Standards Mapping - NIST Special Publication 800-53 Revision 5 SC-2 Separation of System and User Functionality, SI-10 Information Input Validation

[8] Standards Mapping - OWASP API 2023 API3 Broken Object Property Level Authorization

[9] Standards Mapping - OWASP Application Security Verification Standard 4.0 5.1.2 Input Validation Requirements (L1 L2 L3)

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

[11] Standards Mapping - OWASP Top 10 2004 A1 Unvalidated Input

[12] Standards Mapping - OWASP Top 10 2007 A4 Insecure Direct Object Reference

[13] Standards Mapping - OWASP Top 10 2010 A4 Insecure Direct Object References

[14] Standards Mapping - OWASP Top 10 2013 A4 Insecure Direct Object References

[15] Standards Mapping - OWASP Top 10 2017 A5 Broken Access Control

[16] Standards Mapping - OWASP Top 10 2021 A08 Software and Data Integrity Failures

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

[18] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 6.5.2

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

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

[21] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.8

[22] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.8

[23] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.8

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

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

[26] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 5.4 - Authentication and Access Control

[27] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 5.4 - Authentication and Access Control

[28] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 5.4 - Authentication and Access Control, Control Objective C.2.3 - Web Software Access Controls

[29] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[30] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[31] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[32] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[33] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[34] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[35] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[36] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[37] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[38] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[39] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[40] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[41] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[42] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[43] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002150 CAT II, APSC-DV-002560 CAT I

[44] Standards Mapping - Web Application Security Consortium Version 2.00 Insufficient Process Validation (WASC-40)

desc.config.java.mass_assignment_sensitive_field_exposure