Recently, I've been receiving request spikes from requests of the form
Each time the random number is consistent (per 24 hours). On Google analytics I'll suddenly have 300% of my usual entire site traffic directed to a URL that I've no idea what it's attempting to direct to. When I go manually it 404s.
My question is, is this a known hack that indicates that my server is compromised in some way, or otherwise is this something that crawling bots might do?