Malicious Office (OLE) / .XLSX — malware analysis report

Static analysis result for SHA-256 289277c09bcd3254…

MALICIOUS

Office (OLE) / .XLSX

121.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 16f028d2bc8d07b4c16d55082020d63f SHA-1: 3fb12fdd063708932b4c3bd3758b2890d1ef0f01 SHA-256: 289277c09bcd32545f5aaf6971900a41b64a6684c5a7bc091ea797918c5cfdbd
280 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1059.005 Visual Basic

This XLSX file contains VBA macros that trigger on workbook open. The macros display a series of message boxes to the user, seemingly as part of a survey or decision process. Ultimately, the script appears to execute a batch file (`c:\programdata\uidpjewl.bat`) which, in turn, attempts to download and execute payloads from multiple URLs. The presence of `Wscript.Shell` and `CreateObject` calls, along with the `Workbook_Open` auto-execution, strongly suggests a downloader or initial access mechanism.

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.