{
  "family": "bruteforce",
  "sample_count": 13,
  "category": "advanced_threat",
  "description": "HackTool:Win32/Bruteforce (or similar generic designations like 'PasswordCracker') is a heuristic classification used by antivirus and EDR platforms to identify utilities explicitly designed to systematically guess passwords or cryptographic keys. While some of these tools (like Hydra, Hashcat, or Medusa) have legitimate uses in penetration testing and security auditing, they are heavily weaponized by threat actors to achieve initial access or escalate privileges within a compromised network.<br><br><b>Understanding Brute-Forcing Tools</b><br>To a standard user, the execution of a brute-force tool is usually invisible unless it consumes massive CPU/GPU resources. For a security analyst, a 'Bruteforce' alert on a production server or user endpoint is a severe incident. It indicates that an attacker (either an external threat actor who has gained a foothold, or a malicious insider) is actively attempting to break into local accounts, network shares, databases, or web applications by rapidly submitting thousands of password guesses using a predefined dictionary list or algorithmic generation.<br><br><b>Execution and Attack Mechanics</b><br>Attackers deploy brute-force tools during the 'Credential Access' phase of the attack lifecycle. If targeting network services (like RDP, SSH, SMB, or SQL databases), they use tools like Hydra or Ncrack (`T1110.001`). These tools are executed via the command line, pointing them at the target IP address and supplying a username and a massive password list (`rockyou.txt`). The tool rapidly initiates authentication attempts (`T1110.003`). If the attacker has already stolen password hashes (e.g., via dumping the SAM database or NTDS.dit), they will use offline cracking tools like Hashcat or John the Ripper (`T1110.002`), leveraging the infected machine's CPU/GPU to algorithmically guess the plaintext password that generated the hash.<br><br><b>Indicators of Compromise & Impact</b><br>The impact is unauthorized access to sensitive systems, often leading to full domain compromise (Domain Admin access). Incident responders should immediately investigate the source of the alert. If it's a network brute-force attack, Windows Event Logs (Security log) will show a massive spike in Event ID 4625 (Failed Logon) followed by a potential Event ID 4624 (Successful Logon) from a single source IP. If it's an offline cracking attempt, EDR will flag the execution of the cracking utility and anomalous CPU/GPU spikes.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1110.002",
    "T1110.001",
    "T1059.003",
    "T1110.003",
    "T1078"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1110.001",
      "name": "Brute Force: Password Guessing",
      "tactic": "Credential Access"
    },
    {
      "id": "T1110.002",
      "name": "Brute Force: Password Cracking (Offline)",
      "tactic": "Credential Access"
    },
    {
      "id": "T1110.003",
      "name": "Brute Force: Password Spraying",
      "tactic": "Credential Access"
    },
    {
      "id": "T1059.003",
      "name": "Command and Scripting Interpreter: Windows Command Shell",
      "tactic": "Execution"
    },
    {
      "id": "T1078",
      "name": "Valid Accounts (The goal of the attack)",
      "tactic": "Initial Access"
    }
  ],
  "containment_steps": [
    "If the alert indicates an active network brute-force attack, immediately isolate the targeted system or block the source IP address at the firewall.",
    "Analyze Windows Security Event Logs (Event ID 4625) to determine which accounts are being targeted; if a successful login (4624) is found from the attacking IP, consider that account compromised.",
    "If an offline cracking tool (like Hashcat) is found, isolate the machine to determine *how* the attacker obtained the password hashes in the first place (e.g., did they dump LSASS?).",
    "Enforce a mandatory enterprise-wide password reset if Domain Admin hashes were potentially cracked."
  ],
  "what_to_avoid": [
    "Do not ignore the alert simply by deleting the tool; the presence of the tool indicates an attacker is already inside the network attempting to escalate privileges.",
    "Avoid relying solely on account lockouts to stop brute-forcing; modern attackers use 'Password Spraying' (trying one common password across all users) to avoid triggering lockout policies."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}