I also had the same issue (using Debian Jessie and Kernel 4.7.4).
To workaround this, I replaced my netstat-nat (under /usr/bin) with this script:
Code:
#!/usr/bin/perl
print "Proto NATed Address Destination Address State\n";
foreach $line ( `conntrack -g -n -L 2> /dev/null` ) {
chomp( $line );
if( $line =~/(\w+) .* (\w+) src=(\d+.\d+.\d+.\d+) .* sport=(\d+) .* src=(\d+.\d+.\d+.\d+) .* sport=(\d+)/ )
{
print "$1 $3:$4 $5:$6 $2\n";
}
else
{
print "Parse error! orig line = $line";
}
}
I saved this script as /usr/bin/netstat-nat (after backing up the original netstat-nat) and made it an executable (chmod a+x /usr/bin/netstat-nat)
