{
  "author": "ckeller@fusioncybersecurity.us",
  "cat": "New Code Atypical Path",
  "detect": {
    "event": {
      "FILE_PATH": "C:\\Windows\\Temp\\3A22930E-7933-4932-A06B-DA4B7DB2FB1F\\NisSrv.exe",
      "HASH": "28825cafbd9b10716201dcc272e986309f130bee4759dd11aa3812448ab0907f",
      "PROCESS_ID": 17988
    },
    "routing": {
      "arch": 2,
      "did": "",
      "event_id": "eb609401-c258-4958-8b08-b7d0111b9ee8",
      "event_time": 1774468114876,
      "event_type": "NEW_DOCUMENT",
      "ext_ip": "23.128.32.10",
      "hostname": "desktop-3nfb237",
      "iid": "b2cd59fc-d09d-49e0-a9f2-1fd79ee9c175",
      "int_ip": "192.168.50.40",
      "latency": 6216,
      "moduleid": 2,
      "oid": "d3541070-8b0e-4663-8a6a-aa0727aacd36",
      "parent": "9727bc761f07cc5e5c90b93a69c43c07",
      "plat": 268435456,
      "sid": "ed8f7c3f-3a1a-493e-8fa4-35eb8c30b136",
      "tags": [
        "fusion-soc-alert",
        "fusion-soc-case",
        "fusion-soc-pulled",
        "fusion-soc-triage",
        "fusionsoc-critical",
        "fusionsoc-high",
        "fusionsoc-investigated",
        "qucikbooks",
        "windows",
        "yara_detection_memory"
      ],
      "this": "9c74dc570dbd4713e9159e1669c43c18"
    }
  },
  "detect_id": "5d509cad-6388-4b93-bb8a-55ea69c43c19",
  "gen_time": 1774468121092,
  "link": "https://app.limacharlie.io/orgs/d3541070-8b0e-4663-8a6a-aa0727aacd36/sensors/ed8f7c3f-3a1a-493e-8fa4-35eb8c30b136/timeline?time=1774468114\u0026selected=9c74dc570dbd4713e9159e1669c43c18",
  "namespace": "general",
  "routing": {
    "arch": 2,
    "did": "",
    "event_id": "eb609401-c258-4958-8b08-b7d0111b9ee8",
    "event_time": 1774468114876,
    "event_type": "NEW_DOCUMENT",
    "ext_ip": "23.128.32.10",
    "hostname": "desktop-3nfb237",
    "iid": "b2cd59fc-d09d-49e0-a9f2-1fd79ee9c175",
    "int_ip": "192.168.50.40",
    "latency": 6216,
    "moduleid": 2,
    "oid": "d3541070-8b0e-4663-8a6a-aa0727aacd36",
    "parent": "9727bc761f07cc5e5c90b93a69c43c07",
    "plat": 268435456,
    "sid": "ed8f7c3f-3a1a-493e-8fa4-35eb8c30b136",
    "tags": [
      "fusion-soc-alert",
      "fusion-soc-case",
      "fusion-soc-pulled",
      "fusion-soc-triage",
      "fusionsoc-critical",
      "fusionsoc-high",
      "fusionsoc-investigated",
      "qucikbooks",
      "windows",
      "yara_detection_memory"
    ],
    "this": "9c74dc570dbd4713e9159e1669c43c18"
  },
  "source": "d3541070-8b0e-4663-8a6a-aa0727aacd36.b2cd59fc-d09d-49e0-a9f2-1fd79ee9c175.ed8f7c3f-3a1a-493e-8fa4-35eb8c30b136.10000000.2",
  "source_rule": "general.NEW FILE WRITE BYTES SAMPLE GRAB",
  "ts": 1774468121000
}

{
  "virustotal": {
    "malicious": false,
    "provider": "virustotal",
    "reputation": 0,
    "stats": {
      "confirmed-timeout": 0,
      "failure": 0,
      "harmless": 0,
      "malicious": 0,
      "suspicious": 0,
      "timeout": 2,
      "type-unsupported": 4,
      "undetected": 70
    }
  }
}

{
  "confidence": 0.6,
  "false_positive_reason": null,
  "investigation_questions": [],
  "ioc_analysis": "",
  "iocs_extracted": [],
  "mitre_techniques": [],
  "recommended_actions": [
    "Manual analyst review required \u2014 AI models (majority)",
    "Manual review required"
  ],
  "risk_score": 28,
  "severity": "high",
  "summary": "**Vote: MAJORITY (2/3 -\u003e FALSE POSITIVE)**\n\n### \ud83e\udd16 qwen3.5:4b Analysis (Secondary + RAG)\n**Verdict:** false_positive | **Confidence:** 0.95\nThe detection flagged a new file write for NisSrv.exe in the Windows Temp directory, but investigation confirms this is part of legitimate Microsoft Defender Antivirus activity. The process tree shows MpSigStub.exe running under SYSTEM context, which is consistent with normal antivirus scanning behavior.\n\n**IOC Analysis:** NisSrv.exe is a known Microsoft Defender component used for signature updates and scanning. The file location in Windows Temp is typical for temporary extraction of files during scanning operations. The investigation found no suspicious activity and confirmed the process tree matches expected Defender behavior with MpSigStub.exe.\n\n---\n\n### \ud83e\udd16 deepseek-r1:8b Analysis (Secondary + RAG)\n**Verdict:** false_positive | **Confidence:** 0.85\nThe detection flagged a file write in the Windows Temp directory, which is common for legitimate processes but can be exploited. However, the process spawned a benign MpSigStub.exe, and no suspicious activity was found in the investigation window. Historical feedback confirms frequent false positives for this rule.\n\n**IOC Analysis:** FILE_PATH is in C:\\Windows\\Temp, which is not a standard system directory and can be legitimate. HASH is unknown and not verified against known malware databases. The process spawned MpSigStub.exe, a legitimate Microsoft-signed binary, indicating benign activity.",
  "verdict": "false_positive",
  "voting": {
    "auto_action": "manual_review",
    "mode": "majority",
    "total_models": 3,
    "vote_summary": [
      "gemini-cli: true_positive (medium, 0% confidence)",
      "qwen3.5:4b +RAG: false_positive (low, 95% confidence)",
      "deepseek-r1:8b +RAG: false_positive (low, 85% confidence)"
    ],
    "votes": [
      {
        "confidence": 0.0,
        "model": "gemini-cli",
        "verdict": "true_positive"
      },
      {
        "confidence": 0.95,
        "had_rag": true,
        "model": "qwen3.5:4b",
        "verdict": "false_positive"
      },
      {
        "confidence": 0.85,
        "had_rag": true,
        "model": "deepseek-r1:8b",
        "verdict": "false_positive"
      }
    ],
    "winning_count": 2,
    "winning_verdict": "false_positive"
  }
}