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

Static analysis result for SHA-256 05ac5c36c8705660…

MALICIOUS

Office (OLE) / .XLSX

138.0 KB Created: 2022-02-09 09:48:26 Authoring application: Microsoft Excel
MD5: f5ee5fdc004707ad73edc9c9eb050a64 SHA-1: e885d90a896862f2c909617ee84558ebaf0e7854 SHA-256: 05ac5c36c870566085f1609b427b66580e0ad50fea4ecc76def2eee5ecc6adfd
262 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample contains a Workbook_Open VBA macro that utilizes CreateObject to execute code. This macro is designed to download and execute a second-stage payload from one of the 12 embedded URLs. The ClamAV detection name 'Doc.Downloader.EmotetRed02220-9938909-0' further supports its role as a downloader. The presence of VBA macros and the Workbook_Open auto-execution technique strongly indicate a spearphishing attachment attack vector.

Heuristics 7

  • URL reconstructed from VBA cell-staged base64 dropper (12 URLs) critical OLE_VBA_CELL_DROPPER_URL
    VBA reads worksheet cells, strips junk substrings via Replace(), and base64/UTF-16 decodes the result into a PowerShell EncodedCommand payload. The download URL is never contiguous in the file bytes; it was recovered by removing the macro's Replace() junk tokens from the cell strings and decoding the staged base64.
  • ClamAV: Doc.Downloader.EmotetRed02220-9938909-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetRed02220-9938909-0
  • 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.
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code
  • 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://midnightsilvercrafters.com/store/wBjNOUw/
    • http://tempral.com/NATE_05_22_2009/BI710N4cQ6R3/
    • https://redington.karmatechmediaworks.com/wp-content/3JVuVx7QUM/
    • https://uhc.karmatechmediaworks.com/wp-content/0EqfdeznntlOpaIP2Qv/
    • https://servilogic.n
    • https://comezmuhendislik.com/ljfrmm/VTpHRFWoORAHnRQ3aQL/
    • http://webmail.glemedical.com/wp-content/J1M2xxodH/
    • http://toto.karmatechmediaworks.com/wp-content/i826vbcVgRJ/
    • https://golfpia.karmatechmediaworks.com/wp-content/oEicpDnEkk/
    • https://garyjharris.com/cgi-bin/0hH/
    • https://vietnam.karmatechmediaworks.com/wp-content/PfSVQagusZy7AaMw/
    • https://vinculinc.karmatechmediaworks.com/wp-content/VlcOPPwgidWlXDJNs6/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
1dad4823f95a58de9f56d772431a629a3cf404547130fcce04ce47962bf52927
vba-macro oletools.olevba.extract_macros (decoded VBA source) 52352 bytes