On Thu, Jun 02, 2016 at 11:28:40PM +0100, Lisi Reisz wrote: > So far as I can see, ping IS executable by normal users. But then I have > only > got Wheezy and Jessie. Are you using Stretch or Sid??
This is not really new in stretch. You can experiment this funny effect in jessie as well. Try this on a jessie system: cd /bin mv ping ping.old cp ping.old ping Then ping will no longer work for an ordinary user because it lost its "capability", that you can see with getcap this way: getcap ping.old getcap ping It's a funny effect because you will never see the difference by just doing "ls -l". This capability may be lost, for example, if you use rsync to copy the root filesystem to another partition with rsync and forget to use -X option.