When NGINX Plus or NGINX OSS are configured to use the HTTP/3 QUIC module, undisclosed HTTP/3 requests can cause NGINX worker processes to terminate or cause other potential impact. This attack requires that a request be specifically timed during the connection draining process, which the attacker has no visibility and limited influence over.
https://thecyberthrone.in/2024/05/31/nginx-releases-patches-for-several-vulnerabilities/
https://my.f5.com/manage/s/article/K000139611