This fairly low tech DDoS can easily take down an under resourced WordPress website, what you will see in your logs is something like:
/?s=SwCGbtyTPFbgIy | 19:02:40 |
/?s=rNiwiuFckGegR | 19:02:49 |
/?s=SwCGbtyTPFbgIy | 19:02:53 |
/?s=SwCGbtyTPFbgIy | 19:02:56 |
/?s=SwCGbtyTPFbgIy | 19:03:01 |
/?s=mYwyTaXVqvlW | 19:03:12 |
/?s=SwCGbtyTPFbgIy | 19:03:18 |
/?s=mYwyTaXVqvlW | 19:03:22 |