Cisco ASA
TMA-CISCO-ASA-2.5
Ensure ICMP is restricted for untrusted interfaces
Description
Allows ICMP traffic for specific hosts or subnets and denies ICMP traffic for all other sources. ICMP is an important troubleshooting tool that can also be used to perform ICMP attacks on untrusted interfaces. For these interfaces, the ICMP traffic should be allowed only for specific hosts or subnets that are trusted by the Enterprise and should be ... Audited against the output of 'show running-config' (run 'terminal pager 0' first; 'more system:running-config' also works and shows unmasked secrets).
How it is checked
Audit method: Configuration pattern
- Pattern
(?m)^icmp deny any \S+
How it is fixed
Fix method: Guidance or infrastructure patch
! - Step 1: Acquire the untrusted interface name <untrusted_interface_name>, the trusted subnet and corresponding subnet mask - Step 2: Run the following command to allow ICMP from the trusted subnet to the untrusted interface. Repeat the command if there are more than one trusted subnets identified. icmp permit <subnet> <mask> <untrusted_interface_name> - Step 3: Run the following command to deny ICMP from all other sources to the untrusted interface. icmp deny any<untrusted_interface_name>
Properties
- Operating systems
- Any
- Tags
- cisco-asanetworkmanagement-plane
- Reference
- CIS Cisco ASA 9.x Firewall Benchmark v1.1.0 - 2.5 Ensure ICMP is restricted for untrusted interfaces
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target cisco-asa