You cannot decrypt a Type 5 password, however, this article explains how to reset your password using the SolarWinds Cisco Config Uploader.
Type 5 secret passwords use a one-way hash algorithm and cannot be decrypted. However, they can be reset. You can reset a "type 5 secret password" using SolarWinds Cisco Config Uploader. It resets the password via SNMP. All you need is the SNMP read-write community string.