[libvirt] security: the qemu agent command "guest-exec" may cause Insider Access

[Zhangbo (Oscar)]

Hi all:
     The Host Administrator is capable of running any exec in guests via the qemu-ga command "guest-exec", eg:

        virsh qemu-agent-command test_guest '{"execute": "guest-exec", "arguments": {"path": "ifconfig", "arg": [ "eth1", "192.168.0.99" ],"capture-output": true } }'
{"return":{"pid":12425}}
       virsh qemu-agent-command test_guest '{"execute": "guest-exec-status", "arguments": { "pid": 12425 } }'
{"return":{"exitcode":0,"exited":true}}

      The example above just change the guests' ip address, the Administrator may also change guests' user password, get sensitive information, etc. which causes Insider Access.
      The Administrator also can use other commands such as " guest-file-open" that also cause Insider Access.

      So, how to avoid this security problem, what's your suggestion?
      Thanks!

Best Regrads
Oscar