The presence of plaintext strings that can be used to move laterally across the network suggests that passwords or sensitive tokens are stored insecurely. Implementing a password management solution would help mitigate this issue by ensuring that passwords are stored securely and are not exposed in plaintext. Password managers typically use strong encryption to protect stored credentials and provide secure access to them.
Sanitizing user input, rotating keys, and utilizing certificate management address different aspects of security but do not directly resolve the issue of insecure password storage.
Reference:
Importance of password management: NIST Password Guidelines
Examples of security breaches due to poor password management practices: Forge.