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

Static analysis result for SHA-256 d12011f0fa93179e…

MALICIOUS

Office (OOXML) / .XLSX

111.6 KB Created: 2015-06-05 18:17:20 UTC Authoring application: Microsoft Excel 12.0000
MD5: aa43f33ea4e2eab74fedafe7f0e576aa SHA-1: 62c61c1f2b05e9aeb6e727056d2cd72c38fee54f SHA-256: d12011f0fa93179e57934d21a4182f0b2425e1457b1dfe0788054c26384f36ce
260 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.005 Visual Basic T1059.003 Windows Command Shell

The file is an OOXML document containing VBA macros, specifically a Workbook_Open macro, which is a common delivery mechanism for malware. The script attempts to execute a batch file and a VBScript from the 'c:\programdata' directory. The VBScript is obfuscated but appears to be responsible for downloading and executing a second-stage payload from one of the provided URLs. The presence of the 'Doc.Malware.Valyria-10004384-0' ClamAV detection further confirms its malicious nature.

Heuristics 6

  • ClamAV: Doc.Malware.Valyria-10004384-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Malware.Valyria-10004384-0
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • 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
527d0656a0c2c323955d068683ef8f7e20c035cda247a1e24383595c0eb3403b
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 7821 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
c500c7da76dbd4c0262130d90da15a2cd384262f5c53d9230e015935e27a303a
vba-project OOXML VBA project: xl/vbaProject.bin 37888 bytes
Detection
ClamAV: Doc.Malware.Valyria-10004384-0
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.