VirtualBox host-only network, ping works only from guest to host

I have a Windows 7 VM running on a Ubuntu 15.04 host using the latest Virtual Box 5 release. I've configured a host-only network. The configuration of the host-only adapter is:

Adapter IP 192.168.56.1
        Subnetmask 255.255.255.0
DHCP enabled
        Server 192.168.56.100
        Mask 255.255.255.0
        from 192.168.56.101
        to 192.168.56.254

With the adapter being created by VirtualBox, ifconfig vboxnet0 displays:

vboxnet0  Link encap:Ethernet  HWaddr 0a:00:27:00:00:00  
          inet addr:192.168.56.1  Bcast:192.168.56.255  Mask:255.255.255.0
          inet6 addr: fe80::800:27ff:fe00:0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:960 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:112330 (112.3 KB)

The Windows 7 guest receives an IP from the DHCP Server and also seem to have a properly configured interface:

Ethernet adapter Local Area Connection:

   Connection-specific DNS Suffix  . :
   Link-local IPv6 Address . . . . . : fe80::18e1:2f8e:907a:e280%11
   IPv4 Address. . . . . . . . . . . : 192.168.56.101
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . :

The issue I'm currently facing is that I can ping the Ubuntu host from the Windows 7 guest using ping 192.168.56.1. However, I can't ping the guest using ping 192.168.56.101 from my host system. Wireshark tells me that echo requests are sent just fine, but there are no replies coming back. The guest system is a fresh installed Windows 7.

This could be a firewall issue. The Windows 7 firewall blocks ICMP echo requests by default. Try to disable the firewall or to add an exception rule for ICMP echo requests.