"The product contains hard-coded credentials, such as a password or cryptographic key, which it uses for its own inbound authentication, outbound communication to external components, or encryption of internal data." - Entry from the Common Weakness Enumeration
For more info visit <a href="https://cwe.mitre.org/data/definitions/798.html" target="_blank" rel="noopener noreferrer">CWE-798</a>