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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
Showing SKILL.md
Based on SOC occupation classification
| name | cis-ubuntu2004-v300-2-2-4 |
| description | Ensure telnet client is not installed |
| category | cis-networking |
| version | 3.0.0 |
| author | cyberstrike-official |
| tags | ["cis","ubuntu","linux","ubuntu-20.04","services","client","telnet"] |
| cis_id | 2.2.4 |
| cis_benchmark | CIS Ubuntu Linux 20.04 LTS Benchmark v3.0.0 |
| tech_stack | ["ubuntu","linux"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | {} |
The telnet package contains the telnet client, which allows users to start connections to other systems via the telnet protocol.
The telnet protocol is insecure and unencrypted. The use of an unencrypted transmission medium could allow an unauthorized user to steal credentials. The ssh package provides an encrypted session and stronger security and is included in most Linux distributions.
Many insecure service clients are used as troubleshooting tools and in testing environments. Uninstalling them can inhibit capability to test and troubleshoot. If they are required it is advisable to remove the clients after use to prevent accidental or intentional misuse.
Verify telnet is not installed. Use the following command to provide the needed information:
# dpkg-query -s telnet &>/dev/null && echo "telnet is installed"
Nothing should be returned.
Uninstall telnet:
# apt purge telnet
| Controls Version | Control | IG 1 | IG 2 | IG 3 |
|---|---|---|---|---|
| v8 | 4.8 Uninstall or Disable Unnecessary Services on Enterprise Assets and Software Uninstall or disable unnecessary services on enterprise assets and software, such as an unused file sharing service, web application module, or service function. | ● | ● | |
| v7 | 9.2 Ensure Only Approved Ports, Protocols and Services Are Running Ensure that only network ports, protocols, and services listening on a system with validated business needs, are running on each system. | ● | ● |
| Techniques / Sub-techniques | Tactics | Mitigations |
|---|---|---|
| T1040, T1040.000, T1203, T1203.000, T1543, T1543.002 | TA0006, TA0008 | M1041, M1042 |