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

Static analysis result for SHA-256 f542621a42ea43c9…

MALICIOUS

Office (OLE) / .XLS

399.5 KB Created: 2016-11-08 08:33:09 Authoring application: Microsoft Excel First seen: 2022-08-01
MD5: 99019e25bcb406e00a900bf0b2e6e22e SHA-1: 4580abdedc8e71424b888b23ba302e8456c2364d SHA-256: f542621a42ea43c99231122748a874b3a13b0ee98428bbe5a6dc20f4e57ddae4
228 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1059.003 Windows Command Shell T1140 Deobfuscate/Decode Files or Information

The VBA macros within the Excel file contain critical firings for Shell() and WScript.Shell usage, indicating execution of external commands. The script decodes a Base64 string from the document body and saves it as 'nvidiax.exe' in the temporary directory, which is then likely executed. This suggests a downloader or dropper functionality.

Heuristics 6

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • WScript.Shell usage critical OLE_VBA_WSCRIPT
    WScript.Shell usage
  • Reference to Windows Script Host high SC_STR_WSCRIPT
    Reference to Windows Script Host
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code
  • Environ() call (env variable access) low OLE_VBA_ENVIRON
    Environ() call (env variable access)

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
54ba713ab254cfd6176a4b8846c3b0962e2e7a2f34b5c1107ba20bf283bf1595		 vba-macro oletools.olevba.extract_macros (decoded VBA source) 7094 bytes

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