Cobalt Strike: Precise Mapping to 10 Top Level Cyber Threat Clusters

Overview

This analysis maps Cobalt Strike's capabilities to the TLCTC framework, strictly based on the generic vulnerabilities defined for each cluster.

Detailed Cluster Analysis

1. Abuse of Functions

Generic Vulnerability: The scope of software and functions

Capabilities that exploit legitimate functionality:

• PowerShell execution through intended Windows scripting capabilities
• Windows API usage for unintended purposes (e.g., process creation, token manipulation)
• DLL search order manipulation using designed Windows loading behavior
• LOLBins (Living off the Land Binaries) usage leveraging intended system utilities

2. Exploiting Server

Generic Vulnerability: Exploitable flaws in server-side software code

Capabilities targeting server-side vulnerabilities:

• Process injection exploiting server application vulnerabilities
• Service-level vulnerability exploitation
• Web server flaw exploitation through HTTP listeners
• Internal service vulnerability targeting post-compromise

3. Exploiting Client

Generic Vulnerability: Exploitable flaws in client-side software

Capabilities targeting client software vulnerabilities:

• Browser exploit delivery framework
• PDF reader vulnerability exploitation
• Office application vulnerability targeting
• Client application memory corruption exploitation

4. Identity Theft

Generic Vulnerability: Weak identity management processes

Capabilities exploiting identity management weaknesses:

• Token manipulation exploiting session management design
• Kerberos ticket abuse through protocol design weaknesses
• Hash extraction leveraging credential storage weaknesses
• Session token theft exploiting session management flaws

5. Man in the Middle

Generic Vulnerability: Lack of control over communication flow/path

Note: MitM capabilities typically require first achieving position through other clusters:

Capabilities once MitM position is achieved:

• Network traffic interception
• Protocol relay attacks
• SMB traffic manipulation
• HTTP(S) traffic interception

6. Flooding Attack

Generic Vulnerability: Capacity limitations

Note: Cobalt Strike itself lacks a dedicated 'Denial of Service' tool, but its capabilities can be leveraged as components in flooding attacks.

Capabilities that can contribute to resource exhaustion:

• Distributed beacon network coordination for synchronized resource consumption
• Connection flooding through SOCKS proxies when used aggressively
• DNS request amplification through DNS beacons
• Large-scale beacon networks utilizing features like `socks` or `rportfwd` with concurrent connections

7. Malware

Generic Vulnerability: Ability to execute foreign code by design

Core malware capabilities:

• Beacon payload generation and execution
• Shellcode injection into allowed processes
• Custom DLL loading through legitimate mechanisms
• In-memory code execution using permitted frameworks

8. Physical Attack

Generic Vulnerability: Physical accessibility of hardware

Note: Cobalt Strike does not directly orchestrate physical attacks but provides capabilities for exploitation after physical access is achieved through other means.

Relevant post-physical-access capabilities:

• USB drive payload generation for physical media attacks
• Persistence mechanisms following physical access
• Hardware token extraction after physical access
• Support for post-physical-compromise lateral movement

Important: These capabilities are specifically for use after physical access is obtained through other means. Cobalt Strike itself does not facilitate the initial physical access.

9. Social Engineering

Generic Vulnerability: Human gullibility or ignorance

Social engineering support capabilities:

• Phishing email template generation
• Credential harvesting page creation
• Malicious document builders
• Decoy file generation

10. Supply Chain Attack

Generic Vulnerability: Necessary reliance on third-party components

Note: Supply Chain is primarily an initial vector enabling other clusters.

Relevant capabilities:

• Software update server exploitation tools
• Repository compromise frameworks
• Third-party component manipulation utilities

Lateral Movement and Attack Sequences

Lateral Movement Context

Lateral movement represents a combination of techniques where attackers move from initially compromised systems to other targets within a network. Rather than being a distinct threat cluster, lateral movement typically involves chains of multiple threat clusters, most commonly:

• #1 (Abuse of Functions) for leveraging legitimate tools
• #2 (Exploiting Server) for targeting internal services
• #3 (Exploiting Client) for compromising additional endpoints
• #4 (Identity Theft) for credential reuse
• #7 (Malware) for establishing new footholds

Common Attack Sequences

Cobalt Strike operators typically chain multiple threat clusters. Example paths:

1. Initial Access Path:

#9 (Phishing) -> #3 (Client Exploit) -> #7 (Beacon) -> #1 (OS Abuse)

2. Credential-Focused Path:

#9 (Phishing) -> #4 (Identity Theft) -> #1 (Function Abuse) -> #7 (Additional Payloads)

3. Post-Exploitation Path:

#1 (Function Abuse) -> #4 (Identity Theft) -> #5 (MitM) -> #2 (Server Exploit)

Defensive Implications

Understanding this precise mapping enables:

1. Accurate threat modeling for Cobalt Strike campaigns
2. Control implementation targeting specific generic vulnerabilities
3. Detection strategy development based on cluster characteristics
4. Risk assessment aligned with exploitable vulnerabilities

Conclusion

This mapping demonstrates how the TLCTC framework effectively categorizes Cobalt Strike's capabilities while maintaining clear distinctions between different threat types. Each capability is classified based on the primary generic vulnerability it exploits, with attack sequences showing how these capabilities chain together in typical operations.