Could you share or what you expect it to contain? This would help narrow down if it's a specific software patch, a medical document, or a potential security risk.
The specific string may refer to one of the following, depending on where you saw it:
If you encountered "52823.rar" as a download link from an unfamiliar source or in a suspicious email, . Compressed files (RAR, ZIP) are frequently used by threat actors to deliver malware or phishing scripts.