Can't PING domains with ipv6 address

All of a sudden, I can't ping domains with an IPv6 Address. I'm running this command:

 ping google.com

But I don't see anything returned ... it just returns this:

 PING google.com(iad30s15-in-x0e.1e100.net (2607:f8b0:4004:807::200e)) 56 data bytes

And nothing else. I hit CTRL+C to cancel and I get this:

 --- google.com ping statistics ---
 7 packets transmitted, 0 received, 100% packet loss, time 6125ms

I can ping IPv4 addresses just fine. I haven't made any firewall changes. The only changes that have happened on this machine are the usual apt-get update and a reboot.

Here is my firewall settings:

 sudo ufw status verbose
 Status: active
 Logging: on (low)
 Default: deny (incoming), allow (outgoing), disabled (routed)
 New profiles: skip

 To                         Action      From
 --                         ------      ----
 80,443/tcp (Apache Full)   ALLOW IN    Anywhere
 22/tcp (OpenSSH)           ALLOW IN    Anywhere
 25/tcp (Postfix)           ALLOW IN    Anywhere
 22                         ALLOW IN    Anywhere
 80,443/tcp (Apache Full (v6)) ALLOW IN    Anywhere (v6)
 22/tcp (OpenSSH (v6))      ALLOW IN    Anywhere (v6)
 25/tcp (Postfix (v6))      ALLOW IN    Anywhere (v6)
 22 (v6)                    ALLOW IN    Anywhere (v6)

My /etc/hosts/ file:

 cat /etc/hosts
 127.0.0.1 localhost

 # The following lines are desirable for IPv6 capable hosts
 ::1 ip6-localhost ip6-loopback
 fe00::0 ip6-localnet
 ff00::0 ip6-mcastprefix
 ff02::1 ip6-allnodes
 ff02::2 ip6-allrouters
 ff02::3 ip6-allhosts

Network configuration:

 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 
 group default qlen 1000
     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
     inet 127.0.0.1/8 scope host lo
     valid_lft forever preferred_lft forever
 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP 
 group default qlen 1000
     link/ether bc:76:4e:20:2c:c3 brd ff:ff:ff:ff:ff:ff
     inet 104.239.249.27/24 brd 104.239.249.255 scope global eth0
   valid_lft forever preferred_lft forever
inet6 2001:4802:7806:102:be76:4eff:fe20:12b6/64 scope global
   valid_lft forever preferred_lft forever
inet6 2001:4802:7805:103:be76:4eff:fe20:2ccd/64 scope global
   valid_lft forever preferred_lft forever
inet6 fe80::be76:4eff:fe20:2cc3/64 scope link
   valid_lft forever preferred_lft forever
 3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether bc:76:4e:20:2c:f5 brd ff:ff:ff:ff:ff:ff
inet 10.209.160.56/19 brd 10.209.191.255 scope global eth1
   valid_lft forever preferred_lft forever
inet6 fe80::be76:4eff:fe20:2cf5/64 scope link
   valid_lft forever preferred_lft forever

Output of ip -6 route:

 ip -6 route
 2001:4802:7805:103::/64 dev eth0 proto kernel metric 256 pref medium
 2001:4802:7806:102::/64 dev eth0 proto kernel metric 256 pref medium
 fe80::/64 dev eth1 proto kernel metric 256 pref medium
 fe80::/64 dev eth0 proto kernel metric 256 pref medium
 default via fe80::def dev eth0 metric 1024 pref medium

Output of traceroute6:

  traceroute6 google.com
  traceroute to google.com (2607:f8b0:4004:82f::200e) from 
  2001:4802:7806:102:be76:4eff:fe20:12b6, 30 hops max, 24 byte packets
  1  * * *
  2  * * *
  3  * * *

I can ping 2001:4802:7805:103:be76:4eff:fe20:2ccd from my side but cannot 2001:4802:7806:102:be76:4eff:fe20:12b6. And the latter address apparently is used as source address on the outgoing connections (as indicated by traceroute).

There is something wrong with this setup.

You can try to remove the problematic address from your configuration and check if this helps:

ip -6 addr del 2001:4802:7806:102:be76:4eff:fe20:12b6 dev eth0

or something similar, I don't remember from the top of my head.