{
  "author": "ckeller@fusioncybersecurity.us",
  "cat": "New Code Atypical Path",
  "detect": {
    "event": {
      "FILE_PATH": "C:\\Windows\\Temp\\3A22930E-7933-4932-A06B-DA4B7DB2FB1F\\MpCmdRun.exe",
      "HASH": "3b5b209292376581b6effa0037a37cd5f431c9626f079d385761454c039a9912",
      "PROCESS_ID": 17988
    },
    "routing": {
      "arch": 2,
      "did": "",
      "event_id": "67689e46-71e2-47ea-a5e2-9e2f35f601f1",
      "event_time": 1774468112518,
      "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": 3739,
      "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": "e7b5290a9307e383c98404ee69c43c13"
    }
  },
  "detect_id": "b9a21b02-b2b9-4d21-be10-a8d669c43c14",
  "gen_time": 1774468116258,
  "link": "https://app.limacharlie.io/orgs/d3541070-8b0e-4663-8a6a-aa0727aacd36/sensors/ed8f7c3f-3a1a-493e-8fa4-35eb8c30b136/timeline?time=1774468112\u0026selected=e7b5290a9307e383c98404ee69c43c13",
  "namespace": "general",
  "routing": {
    "arch": 2,
    "did": "",
    "event_id": "67689e46-71e2-47ea-a5e2-9e2f35f601f1",
    "event_time": 1774468112518,
    "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": 3739,
    "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": "e7b5290a9307e383c98404ee69c43c13"
  },
  "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": 1774468116000
}

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

{
  "confidence": 0.933,
  "false_positive_reason": "Legitimate system update or maintenance activity staging files in a temporary directory.",
  "investigation_questions": [
    "Was there a simultaneous Windows Defender or Windows Update event recorded in the system logs?",
    "Is the file digitally signed by Microsoft?"
  ],
  "ioc_analysis": "The file \u0027MpCmdRun.exe\u0027 is a known-good Microsoft binary. The path \u0027C:\\Windows\\Temp\\3A22930E-7933-4932-A06B-DA4B7DB2FB1F\\\u0027 is consistent with temporary staging during OS or security software updates. No malicious command-line arguments or anomalous behaviors were associated with this specific file write event.",
  "iocs_extracted": [
    "C:\\Windows\\Temp\\3A22930E-7933-4932-A06B-DA4B7DB2FB1F\\MpCmdRun.exe",
    "3b5b209292376581b6effa0037a37cd5f431c9626f079d385761454c039a9912"
  ],
  "mitre_techniques": [
    "T1059"
  ],
  "recommended_actions": [
    "Close case as false positive (unanimous AI verdict)",
    "Whitelist MpCmdRun.exe in standard Windows temporary update directories if this rule continues to trigger frequently.",
    "Verify the digital signature of the staged binary to ensure it is signed by Microsoft."
  ],
  "risk_score": 10,
  "severity": "low",
  "summary": "**Vote: UNANIMOUS (3/3 -\u003e FALSE POSITIVE)**\n\n### \u264a gemini-cli Analysis (Primary)\n**Verdict:** false_positive | **Confidence:** 0.95\nThe detection triggered on a file write of MpCmdRun.exe in C:\\Windows\\Temp, which is a common staging location for Windows Defender and Windows Update operations. MpCmdRun.exe is a legitimate Microsoft Malware Protection Command Line Utility, and its presence in a GUID-based subdirectory within the Temp folder aligns with standard system maintenance and update behavior.\n\n**IOC Analysis:** The file \u0027MpCmdRun.exe\u0027 is a known-good Microsoft binary. The path \u0027C:\\Windows\\Temp\\3A22930E-7933-4932-A06B-DA4B7DB2FB1F\\\u0027 is consistent with temporary staging during OS or security software updates. No malicious command-line arguments or anomalous behaviors were associated with this specific file write event.\n\n---\n\n### \ud83e\udd16 qwen3.5:4b Analysis (Secondary + RAG)\n**Verdict:** false_positive | **Confidence:** 0.95\nThe detection of MpCmdRun.exe in C:\\Windows\\Temp is a known false positive for Windows Defender update operations. The process is legitimate Microsoft software and the investigation confirmed no suspicious activity.\n\n**IOC Analysis:** MpCmdRun.exe is a legitimate Windows Defender component used for malware protection updates. Its presence in the Temp folder with a GUID subdirectory is standard behavior for Windows Update and Defender maintenance tasks. The associated child process MpSigStub.exe also confirms this as a Microsoft-signed update operation.\n\n---\n\n### \ud83e\udd16 deepseek-r1:8b Analysis (Secondary + RAG)\n**Verdict:** false_positive | **Confidence:** 0.9\nThe detection event flagged a file write of MpCmdRun.exe, a legitimate Microsoft tool for malware protection, in a temporary directory. Investigation confirmed no malicious activity, as it aligns with standard Windows update behavior.\n\n**IOC Analysis:** FILE_PATH: C:\\Windows\\Temp\\... is a common staging location for system updates, and MpCmdRun.exe is a known legitimate binary for Windows Defender. The hash matches a Microsoft-signed file, and no malicious indicators were found. The process spawned MpSigStub.exe, which is also legitimate for update-related tasks.",
  "verdict": "false_positive",
  "voting": {
    "auto_action": "auto_close_fp",
    "mode": "unanimous",
    "total_models": 3,
    "vote_summary": [
      "gemini-cli: false_positive (low, 95% confidence)",
      "qwen3.5:4b +RAG: false_positive (informational, 95% confidence)",
      "deepseek-r1:8b +RAG: false_positive (low, 90% confidence)"
    ],
    "votes": [
      {
        "confidence": 0.95,
        "model": "gemini-cli",
        "verdict": "false_positive"
      },
      {
        "confidence": 0.95,
        "had_rag": true,
        "model": "qwen3.5:4b",
        "verdict": "false_positive"
      },
      {
        "confidence": 0.9,
        "had_rag": true,
        "model": "deepseek-r1:8b",
        "verdict": "false_positive"
      }
    ],
    "winning_count": 3,
    "winning_verdict": "false_positive"
  }
}