Emotet — Office (OOXML) / .XLSX malware analysis

Static analysis result for SHA-256 dbd67cbd0c740527…

MALICIOUS

Office (OOXML) / .XLSX

92.0 KB Created: 2015-06-05 18:17:20 UTC Authoring application: Microsoft Excel 12.0000
MD5: 4cb1718eb777f94dcda473b4f7b2e291 SHA-1: 9ed091aeb363b17845c3a78914ad8706ea595629 SHA-256: dbd67cbd0c740527a7e390654e71d6e38a7186e66fefc1ee54b94ea48ddd51a4
200 Risk Score

Malware Insights

Emotet · confidence 95%

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

The sample contains a Workbook_Open macro, a common Emotet delivery technique. The macro is designed to download and execute a second-stage payload from a series of hardcoded URLs. The DOC BODY contains obfuscated commands that reconstruct the execution command, including the creation of a VBScript file at 'c:\programdata\yhjlswle.vbs' and a batch file at 'c:\programdata\ughldskbhn.bat'. The ClamAV detection name 'Xls.Downloader.EmotetRed02221-9938910-0' further supports the Emotet family attribution.

Heuristics 5

  • ClamAV: Xls.Downloader.EmotetRed02221-9938910-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.EmotetRed02221-9938910-0
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • 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 project inside OOXML medium OOXML_VBA
    Document contains vbaProject.bin — VBA macros present

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
de7bcbc45ff0a77d05d9af662bacc316e71be11a980e94f6673e556a5dd9d1bc
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 12808 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.
vbaProject_00.bin
9630f1c4bb5127b21ad2c497275665164d316620b4213e1194c1604f07df5c83
vba-project OOXML VBA project: xl/vbaProject.bin 37888 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.