CVE 2016-0746
Use-after-free vulnerability in the resolver in nginx 0.6.18 through 1.8.0 and 1.9.x before 1.9.10 allows remote attackers to cause a denial of service (worker process crash) or possibly have unspecified other impact via a crafted DNS response related to CNAME response processing.
See the 
CVE page on Mitre.org
for more details.
