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

Static analysis result for SHA-256 52f5ce9b4a56c31b…

MALICIOUS

Office (OOXML) / .XLSX

111.6 KB Created: 2015-06-05 18:17:20 UTC Authoring application: Microsoft Excel 12.0000
MD5: 40f08e10e9b2b9460ef4fcf17191a2c8 SHA-1: fd1f79362f6c417a0749abb1dad769e9aa0c117b SHA-256: 52f5ce9b4a56c31b668b3c95ca86f59fbb5e47a08983a352507b6c84eb621015
260 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.003 Windows Command Shell T1204.002 Malicious File

The file is identified as malicious by ClamAV with the signature Doc.Malware.Valyria-10004384-0. It contains a Workbook_Open macro that executes obfuscated commands. These commands appear to download and execute a batch file from multiple URLs, including 'http://reumatisminclinic.com/-/-/scCnm3mbJRpsaKBbrC/', and a VBScript from 'c:\programdata\sduoixo.vbs'. The VBA script also attempts to create and run a batch file named 'jledshf.bat' from the 'c:\programdata\' directory.

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
d0d0db14d335f1fef7aaed60f907193f8479fa82c788b22a15ef6fdb003c3fb0
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.