If you must open a RAR file for legitimate reasons, ensure you are using an up-to-date version of WinRAR or 7-Zip to avoid older vulnerabilities in the extraction software itself. Known Exploited Vulnerabilities Catalog - CISA
An attacker who successfully exploits this can gain SYSTEM privileges , the highest level of access on a Windows machine. 23376 rar
Upload the file to a multi-engine scanner like VirusTotal to see if it matches known exploit signatures. If you must open a RAR file for