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

Static analysis result for SHA-256 5a1f70ca78a8b2fe…

MALICIOUS

Office (OLE) / .XLSX

142.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 6c29f0909f310d43208293aeab2d1e07 SHA-1: 3fe30ec7e1ec2e2df4d03446eddb82573d6a5697 SHA-256: 5a1f70ca78a8b2fe459fb3852e3bf6b9ac0917f721f3b79779e4a6bc4b6b0a4a
280 Risk Score

Malware Insights

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

The sample is a macro-enabled Excel file that triggers a Workbook_Open event. This event executes VBA code which utilizes CreateObject to interact with Wscript.Shell and Scripting.FileSystemObject. The script attempts to download and execute a second-stage payload from multiple URLs, including 'http://goyaluaat.vmesha.in/0v6kcnky/CG/'. It also creates batch and VBScript files in 'c:\programdata\'. The VBA code is obfuscated, but the intent to download and execute further malicious content is clear.

Heuristics 7

  • ClamAV: Doc.Malware.Valyria-10004384-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Malware.Valyria-10004384-0
  • 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
527d0656a0c2c323955d068683ef8f7e20c035cda247a1e24383595c0eb3403b
vba-macro oletools.olevba.extract_macros (decoded VBA source) 7821 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.