Intrusion Prevention

Nginx.0-Length.Headers.Leak.DoS

Description

This indicates an attack attempt to exploit a Denial of Service Vulnerability in nginx HTTP Server.
A remote, unauthenticated attacker can exploit this vulnerability on a vulnerable version of Nginx server. By sending a continuous steam of HTTP/2 HEADERS and/or CONTINUATION frames, the attacker can cause a significant resource exhaustion on the target server, and leading to a potential denial-of-service condition especially if a distributed network of source machines are employed.

Affected Products

nginx HTTP Server prior to 1.16.1
nginx HTTP Server prior to 1.17.3

Impact

Denial of Service: Remote attackers can crash vulnerable systems.

Recommended Actions

Apply the most recent upgrade or patch from the vendor.
https://www.nginx.com/blog/nginx-updates-mitigate-august-2019-http-2-vulnerabilities/

CVE References

CVE-2019-9516