According to a recent automated malware analysis report from ANY.RUN , a file named CNI.rar was observed interacting with system processes like WinRAR.exe to perform write operations in a controlled environment.

Providing the source of the file could help narrow down the specific "write-up" you need.

Check the SHA-256 hash on platforms like VirusTotal to see if it matches known infostealers or trojans.

There is currently no widely documented "write-up" for a file named in the context of CTF challenges or standard digital forensics databases. However, recent sandbox reports identify it as a potentially malicious archive. Security Context