CentOS Errata and Enhancement Advisory 2015:1600 

Upstream details at : https://rhn.redhat.com/errata/RHEA-2015-1600.html

The following updated files have been uploaded and are currently 
syncing to the mirrors: ( sha256sum Filename ) 

i386:
d49f85c2013498475e53ac5270c7e582e603eb4ed4d653946aa0143126e8c610  kmod-mac80211_dup-0.1_rh1-1.el6_6.i686.rpm

x86_64:
3285e98c5797bef7fc06d20850fc7f3766d2fdec0348a95085d8780794fb3c7d  kmod-mac80211_dup-0.1_rh1-1.el6_6.x86_64.rpm

Source:
07fdfe64fab5291f1bd3d79ed1a9019670364fb4bdd43d9c2184054fa5a8ab89  mac80211_dup-0.1_rh1-1.el6_6.src.rpm