Emotet — Office (OLE) / .XLSX malware analysis

Static analysis result for SHA-256 bfba734c223a71d8…

MALICIOUS

Office (OLE) / .XLSX

121.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 61cc19e7077fa0cb604807a89c07a0d1 SHA-1: 767bc283a1ba11cbd3d3f6640995e043186c6a77 SHA-256: bfba734c223a71d89ecb7205839e6c36c46d8155350188a340cd6a5b5d3d638c
280 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1059.001 PowerShell T1204.002 Malicious File

The critical ClamAV detection and high-severity heuristics for VBA macros, including Workbook_Open and CreateObject, strongly indicate a malicious macro-based document. The Workbook_Open macro is designed to present multiple message boxes to the user, likely as a lure. The embedded script also contains logic that reconstructs a URL from concatenated strings, which is then used to download and execute a second-stage payload. The reconstructed URL is 'http://lbsbriefs.com/cgi/2kl8X826xEKuehui/', among others, which is a common Emotet delivery technique.

Heuristics 7

  • ClamAV: Xls.Downloader.Emotet-ab81c42b2bd4747e-9951196-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet-ab81c42b2bd4747e-9951196-0
  • Reference to Windows Script Host high SC_STR_WSCRIPT
    Reference to Windows Script Host
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
  • Suspicious extracted artifact high EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
faf50200d5a9adeeda00cc1da1bbf8f6abf0317a1e97a58db8ae804ba12ba446
vba-macro oletools.olevba.extract_macros (decoded VBA source) 13985 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.