F5 NGINX ngx_http_rewrite_module Heap Overflow NGINX Rift Denial of Service Exploit

NGINX Plus and NGINX Open Source have a heap overflow vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when the "rewrite" directive with a query string is followed (in the same location) by the "if" or "set" directive with an unnamed Perl-Compatible Regular Expression (PCRE) capture. An unauthenticated attacker along with conditions beyond its control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. This module will first check if the endpoint given in the ENDPOINT parameter is present. If no parameter is provided, the module will use "/api" as the default value. Then it will send a HTTP request to the endpoint to cause the DoS and try to determine if the attack was successful.