Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 f6317e6ed0e85586…

MALICIOUS

Office (OLE) / .XLS

109.6 KB Created: 2022-01-24 07:24:12 Authoring application: Microsoft Excel
MD5: 44f6691879f1ffcd05fa124fa164acba SHA-1: 30c78e3224170bbfd3ac9f5ad35287ce20184599 SHA-256: f6317e6ed0e855867288e906a7cae696ae91d512ff71afbbbb6736123243329c
200 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV with the signature Xls.Downloader.Emotet-bd646319c2d29cd6-9951195-0. Static analysis revealed the presence of Excel 4.0 macros, specifically an Auto_Open function, which is a known technique for executing malicious code. This function likely downloads and executes a second-stage payload, consistent with Emotet's behavior. The document body content appears to be a generic time card, serving as a lure.

Heuristics 4

  • Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME
    oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • ClamAV: Xls.Downloader.Emotet-bd646319c2d29cd6-9951195-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-bd646319c2d29cd6-9951195-0
  • Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN
    Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
b963fd2c873f3d940f45fa9809347e3e7c13b71fa45fd7358e6000536de179c8		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3607 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.