V-239945

Discussion

Without establishing what type of event occurred, it would be difficult to establish, correlate, and investigate the events leading up to an outage or attack. VPN gateways often have a separate audit log for capturing VPN status and other information about the traffic (as opposed to the log capturing administrative and configuration actions). Audit record content that may be necessary to satisfy this requirement includes, for example, time stamps, source and destination addresses, user/process identifiers, event descriptions, success/fail indications, filenames involved, and access control or flow control rules invoked. Associating event types with detected events in the VPN gateway logs provides a means of investigating an attack, recognizing resource utilization or capacity thresholds, or identifying an improperly configured VPN gateway.

Check Content

Review the ASA configuration to determine if VPN events are logged as shown in the example below.

logging class vpn trap notifications 
logging class vpnc trap notifications 
logging class vpnfo trap notifications 
logging class webfo trap notifications 
logging class webvpn trap notifications 
logging class svc trap notifications

Note: A logging list can be used as an alternative to using class.

If the ASA is not configured to log entries containing information to establish what type of VPN events occurred, this is a finding.