# Usage of custom Digest class

## Overview

* **Rule ID**: `java_lang_information_leakage`
* **Applicable Languages**: Java
* **Weakness ID**: CWE-327

## Description

Creating your own Digest class is discouraged due to the high risk of errors in manually implementing cryptographic functions. It is safer and more secure to use standard Digest algorithms like `SHA-256 or SHA-512`.

## Remediation Guidelines

* **Do not** implement a custom Digest class manually, as it can introduce security vulnerabilities due to incorrect handling or flawed algorithms.
* **Instead, rely on established Digest algorithms** such as `SHA-256, SHA-384, SHA-512, or SHA-512/256`. These standardized algorithms have been extensively tested and are widely trusted for their security.

## References

* [**Java MessageDigest class**](https://docs.oracle.com/en/java/javase/20/docs/api/java.base/java/security/MessageDigest.html)
* [**CWE-327: Use of a Broken or Risky Cryptographic Algorithm**](https://cwe.mitre.org/data/definitions/327.html)
* [**OWASP Top 10: A02:2021 - Cryptographic Failures**](https://owasp.org/Top10/A02_2021-Cryptographic_Failures/)

## Configuration

To omit this rule during a scan, and to provide you with continuous 24/7 code-level scanning, you can employ our [**SAST TOOL**](https://scopy.sec1.io/login)


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