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macOS post-exploitation for credential harvesting, DTrace monitoring, TCC bypass, and stealth operations via native tools
Windows userland post-exploitation for credential harvesting, monitoring, AMSI/ETW bypass, and stealth operations
Kubernetes post-exploitation for container escape, secret extraction, RBAC abuse, and cluster persistence
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Showing SKILL.md
| name | cis-ubuntu2004-v300-4-3-6 |
| description | Ensure nftables loopback traffic is configured |
| category | cis-networking |
| version | 3.0.0 |
| author | cyberstrike-official |
| tags | ["cis","ubuntu","linux","ubuntu-20.04","firewall","nftables"] |
| cis_id | 4.3.6 |
| cis_benchmark | CIS Ubuntu Linux 20.04 LTS Benchmark v3.0.0 |
| tech_stack | ["ubuntu","linux"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | {} |
Configure the loopback interface to accept traffic. Configure all other interfaces to deny traffic to the loopback network
Loopback traffic is generated between processes on machine and is typically critical to the operation of the system. The loopback interface is the only place that loopback network traffic should be seen, all other interfaces should ignore traffic on this network as an anti-spoofing measure.
Run the following commands to verify that the loopback interface is configured: Run the following command to verify the loopback interface is configured to accept network traffic:
nft list ruleset | awk '/hook input/,/}/' | grep 'iif "lo" accept'
Example output:
iif "lo" accept
Run the following command to verify network traffic from an IPv4 loopback interface is configured to drop:
nft list ruleset | awk '/hook input/,/}/' | grep 'ip saddr'
Example output:
ip saddr 127.0.0.0/8 counter packets 0 bytes 0 drop
nft list ruleset | awk '/hook input/,/}/' | grep 'ip6 saddr'
Example output:
ip6 saddr ::1 counter packets 0 bytes 0 drop
Loopback accept rule exists, and drop rules for 127.0.0.0/8 and ::1 are present.
Run the following commands to implement the loopback rules:
nft add rule inet filter input iif lo accept
nft add rule inet filter input ip saddr 127.0.0.0/8 counter drop
nft add rule inet filter input ip6 saddr ::1 counter drop
Not applicable.
v8 - 4.4 Implement and Manage a Firewall on Servers v8 - 4.5 Implement and Manage a Firewall on End-User Devices v7 - 9.4 Apply Host-based Firewalls or Port Filtering
MITRE ATT&CK Mappings: T1562, T1562.004 | TA0005