Info from http://mailman.nginx.org/pipermail/nginx-announce/2016/000179.html :
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Hello!

A problem was identified in nginx code responsible for saving
client request body to a temporary file.  A specially crafted request
might result in worker process crash due to a NULL pointer dereference
while writing client request body to a temporary file (CVE-2016-4450).

The problem affects nginx 1.3.9 - 1.11.0.

The problem is fixed in nginx 1.11.1, 1.10.1.

Patch for nginx 1.9.13 - 1.11.0 can be found here:

http://nginx.org/download/patch.2016.write.txt

Patch for older nginx versions (1.3.9 - 1.9.12):

http://nginx.org/download/patch.2016.write2.txt

-- 
Maxim Dounin
http://nginx.org/
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