Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 e2c5685a02e84597…

MALICIOUS

Office (OLE) / .XLS

70.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-04-22
MD5: a357bebc504584f98c055da7bb5ffedc SHA-1: e69f4ecf95b92f393d8bd374ca02386f79647d1b SHA-256: e2c5685a02e84597e3491708a9e1076ed4104b012c302480bc0a98aa2f6ec90b
200 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open function, which is a known technique for malware delivery. ClamAV detection further confirms its malicious nature, identifying it as Emotet. The macro uses dangerous functions like RUN, suggesting it attempts to execute code. The extracted URLs are likely used to download 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-b3c5cc3b13c03bcc-9950246-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-b3c5cc3b13c03bcc-9950246-0
  • 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
30ada183749f97ebaf18ae6bd28860c0d00794baffcbe6164f1acabbc23f484b
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6769 bytes