CWE-493: Critical Public Variable Without Final Modifier

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Description

The product has a critical public variable that is not final, which allows the variable to be modified to contain unexpected values.

Extended Description

If a field is non-final and public, it can be changed once the value is set by any function that has access to the class which contains the field. This could lead to a vulnerability if other parts of the program make assumptions about the contents of that field.


ThreatScore

Threat Mapped score: 0.0

Industry: Finiancial

Threat priority: Unclassified


Observed Examples (CVEs)

Related Attack Patterns (CAPEC)

N/A


Attack TTPs

N/A

Modes of Introduction

Phase Note
Implementation N/A

Common Consequences

Potential Mitigations

Applicable Platforms


Demonstrative Examples

Intro: Suppose this WidgetData class is used for an e-commerce web site. The programmer attempts to prevent price-tampering attacks by setting the price of the widget using the constructor.

Body: The price field is not final. Even though the value is set by the constructor, it could be modified by anybody that has access to an instance of WidgetData.

public final class WidgetData extends Applet { public float price; ... public WidgetData(...) { this.price = LookupPrice("MyWidgetType"); } }

Intro: Assume the following code is intended to provide the location of a configuration file that controls execution of the application.

Body: While this field is readable from any function, and thus might allow an information leak of a pathname, a more serious problem is that it can be changed by any function.

public string configPath = "/etc/application/config.dat";

Notes

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