Emotet — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 caa12722e0580d23…

MALICIOUS

Office (OLE) / .XLS

72.0 KB Created: 2022-03-30 21:24:25 Authoring application: Microsoft Excel First seen: 2022-03-31
MD5: 1569272900fdd701a0146bcc8cf21317 SHA-1: d456d74701a49751405f7554e1fe461bd7d6d99f SHA-256: caa12722e0580d234e7ae0d8c9e89790425f726d49efefbb2bf3b6d38ad3c845
242 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1218.011 System Binary Proxy Execution: Rundll32 T1059.001 PowerShell

The file contains Excel 4.0 macros, specifically an Auto_Open macro, which is a known technique for executing malicious code. The macro utilizes the `regsvr32.exe` LOLBin to execute a command that appears to download a payload from one of the embedded URLs. ClamAV detection further supports the malicious classification as Emotet. The macro's intent is to download and execute a second-stage payload from the provided URLs.

Heuristics 6

  • 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-b680c97f3ec1c03e-9951030-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-b680c97f3ec1c03e-9951030-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://holidayonehotel.com/libraries/lxek/
    • https://hatipogluhali.com/application/2CkpKEf2H0F/
    • http://e-kinerja.ntbprov.go.id/aset/3yVdAF2bISfGwBmMk/
    • http://https://

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
e342c8d53177c1c3fac8b4b8b2f8c2570c54badc27bdb7b3327aa2bfc5651763
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7272 bytes