The Cisco ASA perimeter firewall must be configured to block all outbound management traffic.
An XCCDF Rule
Description
<VulnDiscussion>The management network must still have its own subnet in order to enforce control and access boundaries provided by Layer 3 network nodes such as routers and firewalls. Management traffic between the managed network elements and the management network is routed via the same links and nodes as that used for production or operational traffic. Safeguards must be implemented to ensure that the management traffic does not leak past the managed network's premise equipment. If a firewall is located behind the premise router, all management traffic must be blocked at that point, with the exception of management traffic destined to premise equipment.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-239867r891331_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Step 1: Configure the ingress ACL similar to the example below.
ASA(config)# access-list INSIDE_IN extended deny udp any any eq snmp
ASA(config)# access-list INSIDE_IN extended deny udp any any eq snmptrap
ASA(config)# access-list INSIDE_IN extended deny udp any any eq ntp
ASA(config)# access-list INSIDE_IN extended deny udp any any eq syslog