Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 71623b0dd1443a27…

MALICIOUS

Office (OLE) / .XLS

80.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-16
MD5: ccd07cbad3f75f8309d4c00d7ba479c2 SHA-1: 8439af12cf8e267d90c4f3d522b2821648607cf0 SHA-256: 71623b0dd1443a27d71ac687c729cda40cf3d6a0d6a78fe4de0765280fd15eb8
200 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The file contains Excel 4.0 macros, specifically an Auto_Open entry that utilizes dangerous functions like RUN. This macro is designed to download and execute a second-stage payload from one of the provided URLs. The ClamAV detection name 'Xls.Downloader.Emotet' strongly suggests the Emotet family.

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