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

Static analysis result for SHA-256 08b6a5aa70405dd9…

MALICIOUS

Office (OOXML) / .XLSM

27.3 KB Created: 2021-08-19 14:03:52 UTC Authoring application: Microsoft Excel 15.0300 First seen: 2022-03-01
MD5: 7041faf49f4055939c08faa5c490cd69 SHA-1: 15da060c453cad20c78ba3da04b06c17a7163a7f SHA-256: 08b6a5aa70405dd991258d4994a6154993dc2be986a95992aa76d5c032b2e2a7
342 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.003 Windows Command Shell T1204.002 Malicious File T1105 Ingress Tool Transfer

The sample is an XLSM file containing a Workbook_Open VBA macro. This macro executes a command using cmd.exe to download a batch file from the URL http://13.231.238.12/dart/IMG-0077520021.bat using certutil and then executes the downloaded file. This indicates a downloader or dropper functionality.

Heuristics 8

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • LOLBin reference in VBA critical OLE_VBA_LOLBIN
    LOLBin reference in VBA
  • ClamAV: Xls.Dropper.EPPlus-9802867-2 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Dropper.EPPlus-9802867-2
  • 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
  • cmd.exe reference in VBA high OLE_VBA_CMD
    cmd.exe reference in VBA
  • VBA project inside OOXML medium OOXML_VBA
    Document contains a VBA project — VBA macros present
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://13.231.238.12/dart/IMG-0077520021.bat

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
ccacf0ce750edeb114de8988b84e1a54602236d2762122130364477d713274b2		 vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 1123 bytes
vbaProject_00.bin
5b8851d4c328bc3360f87303a9da391e945875d5a60ef5e8b89b8e82f224265a		 vba-project OOXML VBA project: xl/vbaProject.bin 5632 bytes
Detection
ClamAV: Xls.Dropper.EPPlus-9802867-2
Obfuscation or payload: unlikely

Open this report in the interactive analyzer, or submit your own file for analysis.