Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 9b35f80f3e2779af…

MALICIOUS

Office (OLE) / .XLS

101.5 KB Created: 2022-04-01 07:14:19 Authoring application: Microsoft Excel First seen: 2022-04-04
MD5: cb5c09b5c29b021f2ba641efbdeedaac SHA-1: 5c8fd2cb05f48ec8e0147c17f8e1f57451249452 SHA-256: 9b35f80f3e2779affa4e38be060d599d2fe625e6de9d01c5d10c2b6c45ffe7a1
200 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Service Execution: Visual Basic T1204.002 Malicious Link: User Execution T1059.001 Command and Scripting Interpreter: PowerShell

The file is an Excel 4.0 macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open macro that uses dangerous functions, specifically the RUN function. The macro constructs URLs by concatenating strings, such as 'http://facts-jo.com/init/jLQY2FpesnIGi0qHqz/', and also reconstructs the command 'regsvr32.exe'. This indicates the macro is designed to download and execute a second-stage payload from the provided URLs.

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-b2cbc93e36c0c13e-9950560-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-b2cbc93e36c0c13e-9950560-0
  • 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
8a188f103ec2ad9c430bbffc369798c3a872a3049e785c27c270542470084682		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7321 bytes

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