具有异常扩展名的归档文件编辑

识别创建的归档文件是否具有异常扩展名。攻击者可能会尝试通过使用图像、音频或文档文件类型使用的文件扩展名值来伪装文件,从而逃避检测。

规则类型:eql

规则索引:

  • logs-endpoint.events.file-*

严重性:低

风险评分: 21

运行间隔:5 分钟

搜索索引的时间范围:now-9m(日期数学格式,另请参阅额外的回溯时间

每次执行的最大警报数: 100

参考:无

标签:

  • 域:终端
  • 操作系统:Windows
  • 用例:威胁检测
  • 战术:防御规避
  • 数据源:Elastic Defend
  • 规则类型:BBR

版本: 2

规则作者:

  • Elastic

规则许可证:Elastic 许可证 v2

规则查询编辑

file where host.os.type == "windows" and event.action != "deletion" and

  /* common archive file headers - Rar, 7z, GZIP, MSCF, XZ, ZIP */
  file.Ext.header_bytes : ("52617221*", "377ABCAF271C*", "1F8B*", "4d534346*", "FD377A585A00*", "504B0304*", "504B0708*") and

  (
    /* common image file extensions */
    file.extension : ("jpg", "jpeg", "emf", "tiff", "gif", "png", "bmp", "ico", "fpx", "eps", "inf") or

    /* common audio and video file extensions */
    file.extension : ("mp3", "wav", "avi", "mpeg", "flv", "wma", "wmv", "mov", "mp4", "3gp") or

    /* common document file extensions */
    (file.extension : ("doc", "docx", "rtf", "ppt", "pptx", "xls", "xlsx") and

    /* exclude ZIP file header values for OPENXML documents */
    not file.Ext.header_bytes : ("504B0304*", "504B0708*"))
  ) and

  not (process.executable : "?:\\Windows\\System32\\inetsrv\\w3wp.exe" and file.path : "?:\\inetpub\\temp\\IIS Temporary Compressed Files\\*")

框架:MITRE ATT&CKTM