: Developers sometimes leave compressed archives of site files on the server, which can contain sensitive database credentials.
Logwatch for linode01.ovirt.org (Linux) - Infra - oVirt List Archives
If your server returned a 404 error (which most do), there is generally no cause for alarm. It simply means a bot knocked on your door and found it locked. However, if you see a 200 status code for a file you didn't intentionally upload, your server may have been compromised or is hosting files you aren't aware of. Best Practices for Webmasters To keep your site safe from these types of automated scans:
: Some specific exploit kits use numbered filenames for their payloads. Why is it in your logs?
The Mystery of 55.rar: Why Your Server Logs Are Seeing This File