https://www.bleepingcomputer.com/news/security/unexplained-noise-storms-flood-the-internet-puzzle-experts/

Internet intelligence firm GreyNoise reports that it has been tracking large waves of "Noise Storms" containing spoofed internet traffic since January 2020. However, despite extensive analysis, it has not concluded its origin and purpose.

These Noise Storms are suspected to be covert communications, DDoS attack coordination signals, clandestine command and control (C2) channels of malware operations, or the result of a misconfiguration.