Please help to identify the following description belonging to which technique in MITRE and the corresponding tactics: FunnyDream can Base64 encode its C2 address stored in a template binary with the `xyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvw_-` or
`xyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvw_=` character sets.