Emotet — Office (OOXML) / .XLSX malware analysis

Static analysis result for SHA-256 1036bc6fff679370…

MALICIOUS

Office (OOXML) / .XLSX

92.0 KB Created: 2015-06-05 18:17:20 UTC Authoring application: Microsoft Excel 12.0000
MD5: 065350a1e4898ac0e0f654e8ec6665e0 SHA-1: 621270382ddb8cc4a7c07b0fc480664542f4a14c SHA-256: 1036bc6fff67937067e16dc4073bacb306d4218b5e5ac74bd04ba89a4f8c60b2
260 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample contains a Workbook_Open macro that is heavily obfuscated and uses CreateObject to execute shell commands. The macro attempts to download and execute a second-stage payload from multiple URLs, including 'http://harperhouseproducts.com/Merchandise2/ARSf1LIcOauh1rDriH/'. The ClamAV signature 'Xls.Downloader.EmotetRed02221-9938910-0' strongly suggests the Emotet family. The obfuscated VBA code and the download mechanism are characteristic of Emotet's downloader functionality.

Heuristics 6

  • Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER
    Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
  • 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
  • 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.
  • VBA project inside OOXML medium OOXML_VBA
    Document contains a VBA project — 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
vbaProject_00.bin
bef300f6cfbac7d38a5073d9783e4cfa0de57a0ff9fe84514bea9d51b61abcf6
vba-project OOXML VBA project: xl/vbaProject.bin 37888 bytes