
Proof-of-concept exploit for CVE-2015-7547 glibc DNS resolver vulnerability. Includes Python and PHP scripts to trigger buffer overflow via crafted DNS responses, with iptables mitigation notes.
https://github.com/fjserna/CVE-2015-7547
So
I tried to see if many things crash on CentOS6.
./CVE-2015-7547-poc.py &
vi /etc/resolve.conf
---------------------------------------------------------------
options single-request-reopen
#nameserver 8.8.8.8
nameserver 127.0.0.1
---------------------------------------------------------------
The PHP function is below
./dns-get.php
iptables
I was able to drop by QTYPE-specific length check, but hmm... Since TCP cannot do length checks, it normally crashes. So it's better to drop TCP by sport.