{
  "family": "mousedisable",
  "sample_count": 2,
  "category": "ransomware",
  "description": "Trojan:Win32/Mousedisable is a heuristic detection for a specific, highly disruptive behavioral trait found in various 'Joke' programs, Lockers, and poorly written Ransomware. As the name implies, its primary function upon execution is to actively hook into the Windows API to intercept and block all input from the victim's mouse and keyboard (`T1562.001`). This essentially paralyzes the user, preventing them from interacting with the operating system to stop the malware or launch diagnostic tools.<br><br><b>Understanding Mousedisable (Input Blockers)</b><br>To an end-user, the computer suddenly freezes; the cursor won't move, and `Ctrl+Alt+Delete` does nothing. For a security analyst, a Mousedisable event indicates a blatant and aggressive attempt by malware to impair defenses and prevent manual remediation (`T1562.001`). This tactic is often a delaying mechanism, used to stall the user while a more destructive payload (like data encryption or exfiltration) executes silently in the background.<br><br><b>Execution and Disruption Mechanics</b><br>Mousedisable behavior is typically implemented using the Windows `SetWindowsHookEx` API. The malware installs a low-level keyboard hook (`WH_KEYBOARD_LL`) and mouse hook (`WH_MOUSE_LL`). When these hooks are in place, the malware intercepts all input events before they reach the intended applications or the OS shell. The malware's hook procedure simply discards the input events, causing the system to ignore the user. To prevent the user from simply rebooting to clear the hook, the malware often establishes persistence (`T1547.001`) to ensure it runs immediately upon the next logon.<br><br><b>Indicators of Compromise & Impact</b><br>The impact is a total, immediate Denial of Service (DoS) for the local user (`T1489`). Host-based IoCs include EDR alerts for 'Suspicious API Hooking' specifically targeting input mechanisms. The primary indicator is the physical manifestation: an unresponsive system that may still be displaying active processes on the screen. Network IoCs are dependent entirely on the secondary payloads the malware might be deploying while the user is locked out.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1489",
    "T1562.001",
    "T1056.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1562.001",
      "name": "Impair Defenses: Disable or Modify Tools (Blocking user input to prevent remediation)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1489",
      "name": "Service Stop (Effectively stopping the user's ability to use the OS)",
      "tactic": "Impact"
    },
    {
      "id": "T1056.001",
      "name": "Input Capture: Keylogging (Using the same hooking mechanism, even if just to discard input)",
      "tactic": "Collection"
    }
  ],
  "containment_steps": [
    "Perform a hard reboot of the machine (hold the power button); if the malware lacks persistence, this will temporarily restore control.",
    "If the malware is persistent, reboot the machine into 'Safe Mode' or use a bootable USB recovery environment to bypass the autorun keys.",
    "Once in a clean environment, use an AV scanner or manually inspect the Registry Run keys to delete the malicious executable.",
    "Investigate EDR telemetry for the time period during which the mouse was disabled to determine if secondary payloads were executed."
  ],
  "what_to_avoid": [
    "Do not assume the computer has simply 'frozen' due to a hardware issue; if this happens repeatedly after booting, it is likely malware.",
    "Avoid leaving the machine running in a locked state; if it's ransomware stalling you, every minute counts. Hard reboot immediately."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}