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

Static analysis result for SHA-256 8d9cb9338d623cce…

MALICIOUS

Office (OLE) / .XLSX

145.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: 26abf9f8cdd9b567bba35cde2f334e97 SHA-1: 1a3f3d4dc394c27da5cee264bb56f0b7335a8151 SHA-256: 8d9cb9338d623cce7e77323efd0a783a34748c2529c252a257977786be5f2067
262 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Service Execution: Visual Basic T1204.002 Malicious File: User Execution: Malicious File

The file contains Excel 4.0 (XLM) macros, specifically an Auto_Open macro that utilizes dangerous functions like RUN. The macros reconstruct and attempt to download payloads from five distinct URLs. The reconstructed string 'DllRegisterServer' and the path 'SysWow64\Windows\' suggest a potential attempt to register a malicious DLL. The ClamAV detection 'Doc.Downloader.EmotetRed02222-9938635-0' further supports its nature as a downloader.

Heuristics 6

  • Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME
    oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • URL reconstructed from XLM cell array (5 URLs) critical OLE_XLM_CELL_ARRAY_URL
    Excel 4.0 macro sheet stages its payload URL across the BIFF8 Shared String Table (one quoted-char SST entry concatenated with & at runtime) or across individual numeric cells (one ASCII charcode per cell). The reconstructed URL is invisible to literal-bytes URL extraction because it is never contiguous in the workbook stream. URLs were recovered by walking the BIFF8 record stream and decoding SST entries plus LABELSST/RK/NUMBER cells.
  • ClamAV: Doc.Downloader.EmotetRed02222-9938635-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetRed02222-9938635-0
  • Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN
    Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.
  • 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 https://teamsandeep.com/wp-content/p3f2n6wc4nwfg/
    • https://csinoticias.com/wp-includes/RnHjIzg/
    • http://landorestates.com/wordpress/NELf96wr/
    • https://www.rockwoodsaloon.com/wp-admin/A706GTXNufQSWXG52/
    • http://butziger.com/meettiming/hBJCeNGAvBpGZoD7ee/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
71a011c6654bf0f86fe42dabbb7815a8e04c6ae15b5b70864945acbb6f82ced0		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6768 bytes

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