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

Static analysis result for SHA-256 774799ed1b73fe1c…

MALICIOUS

Office (OLE) / .XLS

426.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: ad1550e4039b1e8c4b8840b839ed4c0b SHA-1: d22304a52ba546cbfd587b6235546c8f68a9d338 SHA-256: 774799ed1b73fe1cf451d0f1150fac0e71b1b50ded4a67ada1be767e97f85a26
382 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File

The sample contains both VBA and Excel 4.0 (XLM) macros. The XLM macros are configured to execute automatically upon opening the workbook, utilizing functions like RUN to download content from the URL 'https://www.notamuzikaletleri.com/19.gif'. The Workbook_Open VBA macro also attempts to close the application, likely to conceal execution. The presence of both macro types and the explicit URL download function strongly indicate a downloader or initial-stage payload.

Heuristics 10

  • Reference to URLDownloadToFile API critical SC_STR_URLDOWNLOAD
    Reference to URLDownloadToFile API
  • 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 (1 URL) 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.
  • Reference to ShellExecute API high SC_STR_SHELLEXEC
    Reference to ShellExecute API
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • 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.
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • 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://www.notamuzikaletleri.com/19.gif
    • https://www.notamuzikaletleri.com/19.gif�
    • http://ns.adobe.com/xap/1.0/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/sType/ResourceRef#
    • http://purl.org/dc/elements/1.1/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
e26e570691e37538cb153a294d4bd7899ebc79f39ec63fd34cf1eae37efa26f6
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 9455 bytes
macros.bas
8c21c322bb8b23e7dbfa4da0de1c41676162b0810e96582d1365413c12adc768
vba-macro oletools.olevba.extract_macros (decoded VBA source) 977 bytes