COMMON WEAKNESS ENUMERATIONDraft

CWE-547

Use of Hard-coded, Security-relevant Constants

The product uses hard-coded constants instead of symbolic names for security-critical values, which increases the likelihood of mistakes during code maintenance or security policy change.

Abstraction

Base

Structure

Simple

Likelihood of Exploit

Medium

Understand the problem

What is the problem?

The product uses hard-coded constants instead of symbolic names for security-critical values, which increases the likelihood of mistakes during code maintenance or security policy change.

Extended description

If the developer does not find all occurrences of the hard-coded constants, an incorrect policy decision may be made if one of the constants is not changed. Making changes to these values will require code changes that may be difficult or impossible once the system is released to the field. In addition, these hard-coded values may become available to attackers if the code is ever disclosed.

Root cause

How and when does the problem arise?

Lifecycle phase

Implementation

Risk

What does successful exploitation lead to?

Varies by ContextQuality DegradationReduce Maintainability

Affected security scopes: Other

The existence of hardcoded constants could cause unexpected behavior and the introduction of weaknesses during code maintenance or when making changes to the code if all occurrences are not modified. The use of hardcoded constants is an indication of poor quality.

Defence

How is it prevented and fixed?

Implementation

Implementation-phase defence

Detail
Avoid using hard-coded constants. Configuration files offer a more flexible solution.

Verification

How is it detected?

Automated Static Analysis

High
Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)