TLCTC Blog - 2025/04/07

The Challenge

The cybersecurity landscape faces a critical challenge: fragmented threat intelligence that fails to effectively connect strategic risk management with operational security execution. While frameworks like MITRE ATT&CK and STIX enable detailed threat intelligence sharing, they lack a standardized high-level threat categorization system that aligns threat intelligence with risk management and security operations.

Framework Benefits

The 10 Top Level Cyber Threat Clusters (TLCTC) framework, utilizing the TLCTC-XX.YY standardized enumeration, addresses this gap by providing a comprehensive solution that bridges threat intelligence with practical security implementation.

• Universal Taxonomy: Establishes a standardized system (TLCTC-XX.YY) for consistent threat intelligence collection and sharing across organizations and sectors. The `.00` suffix denotes the top-level cluster, allowing for future refinement (e.g., TLCTC-08.01 for Direct Physical Access).
• Intelligence-Vulnerability Mapping: Creates clear connections between threat intelligence indicators and generic vulnerabilities, enabling more effective risk assessment.
• Control Implementation Methodology: Provides a structured approach for translating threat intelligence into specific control requirements and implementation guidelines.
• Unified Communication: Establishes a common language using standardized identifiers between threat intelligence teams, risk managers, and security operations personnel.

Integration Benefits

By integrating this framework with established standards like MITRE ATT&CK and STIX, organizations can transform raw threat intelligence into actionable insights that drive both strategic risk decisions and tactical security operations. This integration enables:

• Enhanced Threat Hunting: More effective identification and tracking of potential threats across the environment using consistent identifiers.
• Precise Control Selection: Better alignment between identified threats (e.g., TLCTC-07.00) and necessary security controls.
• Comprehensive Incident Response: More thorough and effective incident response planning and execution based on clear attack sequence understanding (e.g., #09 -> #03 -> #07).
• Lifecycle Consistency: Maintained consistency across the entire threat intelligence lifecycle, from collection to action.

{
  "type": "x-threat-cluster",
  "spec_version": "2.1",
  "id": "x-threat-cluster--[UUID-for-TLCTC-01.00]", // Standard STIX ID
  "created": "2025-03-29T10:00:00.000Z",
  "modified": "2025-03-29T10:00:00.000Z",
  "name": "Abuse of Functions (TLCTC-01.00)",
  "x_tlctc_id": "TLCTC-01.00", // Standardized TLCTC Identifier
  "description": "Abuse of Functions involves manipulating the intended functionality of software or systems for malicious purposes",
  "x_generic_vulnerability": "The scope, complexity, or inherent trust placed in legitimate software functions, features, and configurations.",
  "x_asset_type": "Software (Its functions and configuration)",
  "x_attacker_perspective": "I abuse a functionality, not a coding issue."
}

{
  "type": "x-attack-sequence",
  "spec_version": "2.1",
  "id": "x-attack-sequence--[UUID-for-SEQ001]", // Standard STIX ID
  "created": "2025-03-29T10:05:00.000Z",
  "modified": "2025-03-29T10:05:00.000Z",
  "name": "Phishing to Malware Chain (SEQ001)",
  "x_sequence_notation": "#09 -> #03 -> #07", // Human-readable sequence
  "initial_cluster_ref": "x-threat-cluster--[UUID-for-TLCTC-09.00]", // Ref to STIX object
  "x_initial_cluster_tlctc_id": "TLCTC-09.00", // Corresponding TLCTC ID
  "subsequent_cluster_refs": [
    "x-threat-cluster--[UUID-for-TLCTC-03.00]", // Ref to STIX object
    "x-threat-cluster--[UUID-for-TLCTC-07.00]"  // Ref to STIX object
  ],
  "x_subsequent_clusters_tlctc_ids": [
     "TLCTC-03.00",
     "TLCTC-07.00"
  ],
  "observed_frequency": "high",
  "first_observed": "2024-01-01T00:00:00Z",
  "last_observed": "2025-03-28T00:00:00Z",
  "x_description": "Common attack path starting with social engineering leading to client exploitation and malware deployment."
}

{
  "type": "attack-pattern",
  "spec_version": "2.1",
  "id": "attack-pattern--[UUID-for-Spearphishing]", // Standard STIX ID
  "created": "2025-03-29T10:10:00.000Z",
  "modified": "2025-03-29T10:10:00.000Z",
  "name": "Spearphishing Attachment",
  "description": "Adversaries may send spearphishing emails with malicious attachments, often leading to client exploitation or malware execution.",
  "kill_chain_phases": [{
    "kill_chain_name": "mitre-attack", // Or other kill chain models
    "phase_name": "initial-access"
  }],
  "external_references": [ // Link to MITRE ATT&CK Tactic/Technique if applicable
     {"source_name": "mitre-attack", "external_id": "T1566.001", "url": "..."}
  ],
  "x_tlctc_mapping": { // Custom extension for TLCTC context
    "primary_cluster_ref": "x-threat-cluster--[UUID-for-TLCTC-09.00]",
    "primary_cluster_tlctc_id": "TLCTC-09.00", // Social Engineering
    "typical_followup_cluster_refs": [
      "x-threat-cluster--[UUID-for-TLCTC-03.00]", // Exploiting Client
      "x-threat-cluster--[UUID-for-TLCTC-07.00]"  // Malware
    ],
    "typical_followup_clusters_tlctc_ids": [
      "TLCTC-03.00",
      "TLCTC-07.00"
    ],
    "typical_sequence_notation": "#09 -> #03 -> #07",
    "attack_phase_relevance": ["Initial Access", "Execution (via user interaction)"]
  }
}

{
  "type": "x-attack-sequence",
  "spec_version": "2.1",
  "id": "x-attack-sequence--[UUID-for-Emotet-Example]",
  "created": "2025-03-29T11:00:00.000Z",
  "modified": "2025-03-29T11:00:00.000Z",
  "name": "Emotet Initial Access to Domain Compromise and Ransomware",
  "x_sequence_notation": "#09 -> #07 -> #07 -> #04 -> (#01 + #07)",
  "initial_cluster_ref": "x-threat-cluster--[UUID-for-TLCTC-09.00]",
  "x_initial_cluster_tlctc_id": "TLCTC-09.00", // Social Engineering
  "subsequent_cluster_refs": [
    "x-threat-cluster--[UUID-for-TLCTC-07.00]", // Malware (Emotet loader)
    "x-threat-cluster--[UUID-for-TLCTC-07.00]", // Malware (Trickbot)
    "x-threat-cluster--[UUID-for-TLCTC-04.00]", // Identity Theft (Cred stealing)
    // Representing parallel execution requires relationships or a more complex object structure.
    // For simplicity here, we list the involved cluster object refs.
    "x-threat-cluster--[UUID-for-TLCTC-01.00]", // Abuse of Functions (Lateral via creds)
    "x-threat-cluster--[UUID-for-TLCTC-07.00]"  // Malware (Ryuk Ransomware)
  ],
  "x_subsequent_clusters_tlctc_ids": [ // Reflecting the sequence steps
     "TLCTC-07.00",
     "TLCTC-07.00",
     "TLCTC-04.00",
     ["TLCTC-01.00", "TLCTC-07.00"] // Indicating the parallel step
  ],
  "x_description": "Typical Emotet attack involving phishing, multiple malware stages, credential theft, lateral movement using abused functions, and final ransomware deployment.",
  "observed_frequency": "medium" // Example frequency
}