Check: CASA-ND-000940
Cisco ASA NDM STIG:
CASA-ND-000940
(in versions v2 r2 through v1 r1)
Title
The Cisco ASA must be configured to synchronize its clock with the primary and secondary time sources using redundant authoritative time sources. (Cat II impact)
Discussion
The loss of connectivity to a particular authoritative time source will result in the loss of time synchronization (free-run mode) and increasingly inaccurate time stamps on audit events and other functions. Multiple time sources provide redundancy by including a secondary source. Time synchronization is usually a hierarchy; clients synchronize time to a local source while that source synchronizes its time to a more accurate source. The network device must utilize an authoritative time server and/or be configured to use redundant authoritative time sources. This requirement is related to the comparison done in CCI-001891. DOD-approved solutions consist of a combination of a primary and secondary time source using a combination or multiple instances of the following: a time server designated for the appropriate DOD network (NIPRNet/SIPRNet); United States Naval Observatory (USNO) time servers; and/or the Global Positioning System (GPS). The secondary time source must be located in a different geographic region than the primary time source.
Check Content
Review the Cisco ASA configuration to verify it is compliant with this requirement as shown in the configuration example below. ntp server 10.1.22.2 ntp server 10.1.48.8 prefer Note: For ASAs running on Firepower Chassis hardware, the NTP settings are visible in the FXOS web UI only (not in the ASA CLI or ASDM web UI). If the Cisco ASA is not configured to synchronize its clock with redundant authoritative time sources, this is a finding.
Fix Text
Configure the Cisco ASA to synchronize its clock with redundant authoritative time sources as shown in the example below. ASA(config)# ntp server 10.1.48.8 prefer ASA(config)# ntp server 10.1.22.2 ASA(config)# end
Additional Identifiers
Rule ID: SV-239924r1015262_rule
Vulnerability ID: V-239924
Group Title: SRG-APP-000373-NDM-000298
Expert Comments
CCIs
| Number | Definition |
|---|---|
| CCI-001890 |
Record time stamps for audit records that use Coordinated Universal Time, have a fixed local time offset from Coordinated Universal Time, or that include the local time offset as part of the time stamp. |
| CCI-001893 |
The information system identifies a secondary authoritative time source that is located in a different geographic region than the primary authoritative time source. |
| CCI-004922 |
Synchronize system clocks within and between systems or system components. |
| CCI-004923 |
Compare the internal system clocks on an organization-defined frequency with organization-defined authoritative time source. |
| CCI-004928 |
Identify a secondary authoritative time source that is in a different geographic region than the primary authoritative time source. |