6.1 Enable bidirectional CHAP authentication for iSCSI traffic.

Information

By enabling bidirectional CHAP, also known as Mutual CHAP, an additional level of security
enables the initiator to authenticate the target.

*Rationale*

vSphere allows for the use of bidirectional authentication of both the iSCSI target and host.
Choosing not to enforce more stringent authentication can make sense if you create a
dedicated network or VLAN to service all your iSCSI devices. By not authenticating both the
iSCSI target and host, there is a potential for a MiTM attack in which an attacker might
impersonate either side of the connection to steal data. Bidirectional authentication can
mitigate this risk. If the iSCSI facility is isolated from general network traffic, it is less
vulnerable to exploitation.

Solution

Perform the following-
1. From the vSphere Web Client, navigate to 'Hosts'.
2. Click on a host.
3. Click on 'Manage' -> 'Storage' -> 'Storage Adapters'.
4. Select the iSCSI adapter to configure OR click the green plus symbol to create a new
adapter.
5. Under Adapter Details, click the Properties tab and click 'Edit' in the Authentication
panel.
6. Specify authentication method- 'Use bidirectional CHAP'.
7. Specify the outgoing CHAP name.
o Make sure that the name you specify matches the name configured on the
storage side.
. To set the CHAP name to the iSCSI adapter name, select Use initiator
name.
. To set the CHAP name to anything other than the iSCSI initiator name,
deselect Use initiator name and type a name in the Name text box.8. Enter an outgoing CHAP secret to be used as part of authentication. Use the same
secret as your storage side secret.
9. Specify incoming CHAP credentials. Make sure your outgoing and incoming secrets
do not match.
10. Click OK.
11. Click the second to last symbol to rescan the iSCSI adapter.To implement the recommended configuration state, run the following PowerCLI
command-# Set the Chap settings for the Iscsi Adapter
Get-VMHost | Get-VMHostHba | Where {$_.Type -eq 'Iscsi'} | Set-VMHostHba # Use desired
parameters here

Default Value-The prescribed state is not the default state.

See Also

https://workbench.cisecurity.org/files/145

Item Details

Category: IDENTIFICATION AND AUTHENTICATION

References: 800-53|IA-3(1)

Plugin: VMware

Control ID: 7a4c2164079a8f363a53f8b3e36608abc26b217fc0b8aa488bd0952e710d324c