Information
The <credentials> element of the <authentication> element allows optional definitions of name and password for IIS Manager User accounts within the configuration file. Forms based authentication also uses these elements to define the users. IIS Manager Users can use the administration interface to connect to sites and applications in which they've been granted authorization. Note that the <credentials> element only applies when the default provider, ConfigurationAuthenticationProvider, is configured as the authentication provider. It is recommended that passwordFormat be set to a value other than Clear, such as SHA1.
Rationale:
Authentication credentials should always be protected to reduce the risk of stolen authentication credentials.
Solution
Authentication mode is configurable at the machine.config, root-level web.config, or application-level web.config:
Locate and open the configuration file where the credentials are stored
Find the <credentials> element
If present, ensure passwordFormat is not set to Clear
Change passwordFormat to SHA1
The clear text passwords will need to be replaced with the appropriate hashed version.