This has been happening for a few days on my end. If it is a DDoS attack, it's likely looking for weaknesses in the system. Buffer overflows can reveal a lot of openings in a server if it isn't up to snuff.
But the sad h.A.m. cartels could also be a source, as you say, or even this rogue scraperbot. I have made lots of scrapers for different reasons and none has ever gone rogue on me. Then again, maybe I was just careful. Who knows?
My Source: 25+ years of IT security and systems management with coding in assembly, basic, rust, c/c++ experience under Windows/Windows NT since 3.1 and Linux since 1996 when it was just a hobby