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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
Based on SOC occupation classification
Showing SKILL.md
| name | cis-gcp-cos-3.2.3 |
| description | Ensure secure ICMP redirects are not accepted |
| category | cis-gcp-cos |
| version | 1.2.0 |
| author | cyberstrike-official |
| tags | ["cis","gcp","container-optimized-os","network","sysctl","icmp","routing"] |
| cis_id | 3.2.3 |
| cis_benchmark | CIS Google Container-Optimized OS Benchmark v1.2.0 |
| tech_stack | ["gcp","linux"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | {} |
Secure ICMP redirects are the same as ICMP redirects, except they come from gateways listed on the default gateway list. It is assumed that these gateways are known to your system, and that they are likely to be secure.
It is still possible for even known gateways to be compromised. Setting net.ipv4.conf.all.secure_redirects to 0 protects the system from routing table updates by possibly compromised known gateways.
Run the following commands and verify output matches:
# sysctl net.ipv4.conf.all.secure_redirects
net.ipv4.conf.all.secure_redirects = 0
# sysctl net.ipv4.conf.default.secure_redirects
net.ipv4.conf.default.secure_redirects = 0
Both sysctl commands should return a value of 0, confirming that secure ICMP redirects are not accepted.
Run the following commands to set the active kernel parameters:
# sysctl -w net.ipv4.conf.all.secure_redirects=0
# sysctl -w net.ipv4.conf.default.secure_redirects=0
# sysctl -w net.ipv4.route.flush=1
/etc is stateless on Container-Optimized OS. Therefore, /etc cannot be used to make these changes persistent across reboots. The steps mentioned above needs to be performed after every boot.
| Controls Version | Control | IG 1 | IG 2 | IG 3 |
|---|---|---|---|---|
| v8 | 12.2 Establish and Maintain a Secure Network Architecture - Establish and maintain a secure network architecture. A secure network architecture must address segmentation, least privilege, and availability, at a minimum. | X | X | |
| v7 | 5.1 Establish Secure Configurations - Maintain documented, standard security configuration standards for all authorized operating systems and software. | X | X | X |