{
  "family": "kates",
  "sample_count": 2,
  "category": "trojan",
  "description": "Virus:Win32/Kates is a parasitic file infector virus that specifically targets executable files (`.exe` and `.dll`) on the compromised system. Unlike a trojan that acts as a standalone application, Kates physically modifies legitimate system and application files, injecting its malicious code into them to ensure execution whenever the user runs normal software, making removal incredibly difficult without damaging the OS.<br><br><b>Understanding Kates (File Infectors)</b><br>To an end-user, a Kates infection might manifest as generalized system instability, application crashes, or slow performance as the virus aggressively modifies files in the background. For an incident response team, a file infector is a worst-case scenario. It does not just establish a single persistence mechanism (`T1547`); it turns hundreds of legitimate applications into vectors for its propagation and payload execution (`T1546.008`).<br><br><b>Execution and Infection Mechanics</b><br>Upon initial execution (often via a drive-by download or infected software bundle), Kates actively scans local and mapped network drives (`T1083`) for executable files. It utilizes advanced PE (Portable Executable) infection techniques, appending its code to the target file and modifying the Entry Point (OEP) to ensure the virus runs first. When the user launches the infected application, the Kates code executes, attempts to propagate further, connects to a C2 server (often to download a secondary payload like a botnet agent or password stealer - `T1105`), and then passes control back to the legitimate application to mask its presence.<br><br><b>Indicators of Compromise & Impact</b><br>The impact is widespread system corruption and potential data theft. Host-based IoCs include EDR alerts for mass file modification, unexpected changes to the hash values and file sizes of core system utilities (like `notepad.exe` or `calc.exe`), and legitimate applications making anomalous outbound network connections. Memory analysis will reveal malicious threads executing within the context of verified Microsoft binaries.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1546.008",
    "T1105",
    "T1083"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1546.008",
      "name": "Event Triggered Execution: File Infection (PE Injection)",
      "tactic": "Persistence"
    },
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer (Downloading secondary payloads)",
      "tactic": "Command and Control"
    },
    {
      "id": "T1083",
      "name": "File and Directory Discovery (Scanning for executables to infect)",
      "tactic": "Discovery"
    }
  ],
  "containment_steps": [
    "IMMEDIATELY isolate the infected machine from the network; file infectors will aggressively target and corrupt executables on open network shares.",
    "Do not attempt to manually delete infected system files, as this will render the operating system unbootable.",
    "Use a specialized, bootable offline AV scanner (like Windows Defender Offline) to attempt to clean and repair the infected PE files without the virus running in memory.",
    "If the infection is widespread, the only reliable remediation is a complete wipe and re-image of the system."
  ],
  "what_to_avoid": [
    "Do not back up executable files from an infected machine; you will just back up the virus and reinfect the system upon restoration.",
    "Avoid relying on standard, running-OS antivirus removal tools; Kates actively protects its processes and will re-infect files as they are cleaned."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}