Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 7e56aa9594e4d5cb…

MALICIOUS

Office (OLE) / .XLS

74.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-20
MD5: d1f5231672a26cf75b78eed413e3d5a1 SHA-1: a825af2ba8c3b059cd76ee5d8fe21a7e3f31a74a SHA-256: 7e56aa9594e4d5cb5c648914d5419d87215b2b0b2c9badfcdd10af758ab059f5
200 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The sample is an Excel file containing Excel 4.0 macros, specifically an Auto_Open macro, which is a known technique for executing malicious code upon opening. The macros utilize dangerous functions and are detected by ClamAV as Emotet, a downloader family. The extracted URLs are likely used to fetch and execute a second-stage payload.

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-ea81817e7f807ab1-9952142-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-ea81817e7f807ab1-9952142-0
  • 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
7ab5ef6689937532951c996fe211a2ac046a3dbc546728bfe725212729605929
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6790 bytes