Ghost gethost attack

[American Sentry Systems, Inc.]

I just read in a security tade journal about the "Ghost" attach.  I 
seems that it stems from the glibc library.  I was surprised that not 
much was mentioned about since the security concerns were announced in 
January, 2015.  It seems that Ubuntu 14.04 fixed the issue but 12.04 did 
not.  Between that I did not see clear documentation.

My question: Can I just check the date of the glibc file on my computer, 
and if it is not of a certain date, then replace it?  My issue is that 
some of my computers are running 14.04, but one is not, and I am unable 
to upgrade it, as when I did, things stopped working and it moved the 
prior version to a different filesystem, from which I use the computer.

tia,

John