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。

Unsafe Mobile Code: Unsafe Public Field

Java/JSP

Abstract

程式聲明成員變數 public，而不是 final，因此違反了行動程式碼的安全編碼原則。

Explanation

在 Applet 和其所使用的類別中，所有 public 成員變數都應該聲明 final，以避免攻擊者未經授權竄改或取得對 Applet 內部狀態的存取權。

範例 1：下列 Java Applet 程式碼錯誤地把成員變數聲明為 public，而不是 final。


public final class urlTool extends Applet {
public URL url;
	...
}

行動程式碼，在這個示例中也就是 Java Applet，是一種跨網路傳輸，並且可在遠端機器上執行的程式碼。因為行動程式碼的編寫者很難控制他們編寫的程式碼的執行環境，所以在安全上提出特別的要求是有必要的。其中一個最大的環境威脅在於，行動程式碼可以伴隨著其他的潛在惡意的行動程式碼一起運作。因為所有主流的瀏覽器會使用同一個 JVM 執行來自多個資源的程式碼，所以許多安全規範都把注意力集中在可以存取您的程式碼運行的 JVM 攻擊者，避免他們竄改您的物件狀態和運作方式。

References

[1] G. McGraw Securing Java. Chapter 7: Java Security Guidelines

[2] MUTABLE-8: Define wrapper methods around modifiable internal state Oracle

[3] Standards Mapping - Common Weakness Enumeration CWE ID 493

[4] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-000213, CCI-002165

[5] Standards Mapping - NIST Special Publication 800-53 Revision 4 AC-3 Access Enforcement (P1)

[6] Standards Mapping - NIST Special Publication 800-53 Revision 5 AC-3 Access Enforcement

[7] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.8

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

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

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

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

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

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

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

[15] 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

[16] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[17] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[18] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[19] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[20] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[21] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[22] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[23] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[24] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[25] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[26] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[27] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[28] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[29] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[30] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-000460 CAT I, APSC-DV-000470 CAT II

[31] Standards Mapping - Web Application Security Consortium Version 2.00 Insufficient Authorization (WASC-02)

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