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

Static analysis result for SHA-256 af5b6726d3509c8f…

MALICIOUS

Office (OLE) / .XLS

62.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 83210cb6f84d46fee8980be84d1af519 SHA-1: 81d385a0a9c23c2f46863a1b16be8cb4d3d4febf SHA-256: af5b6726d3509c8f4f580609bb764ac22fae56956bcd275fb8b011ae17f85899
240 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1059.004 PowerShell T1059.001 PowerShell T1204 User Execution

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. It contains a Workbook_Open macro and uses the ShellExecute and URLDownloadToFile APIs, indicating an intent to download and execute a secondary payload. The document body also contains an embedded URL, likely used for this purpose. The presence of XLM macros and the use of ShellExecute and URLDownloadToFile are strong indicators of a downloader or droppper functionality.

Heuristics 8

  • Reference to URLDownloadToFile API critical SC_STR_URLDOWNLOAD
    Reference to URLDownloadToFile API
  • Reference to ShellExecute API high SC_STR_SHELLEXEC
    Reference to ShellExecute API
  • XLM Auto_Open with dangerous formula APIs high 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.
  • 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 http://blog.vokasidev.com/crun20.gif�
    • http://blog.vokasidev.com/crun20.gif

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
d4222e1ad83b892546402a65bce1342319760d5f0e17d0c73ae5f07e792beb86
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 9447 bytes
macros.bas
c29faf2da8b6b84c63880f8f3ff09f138acdaa94ad9406cab75b546ae0e54428
vba-macro oletools.olevba.extract_macros (decoded VBA source) 979 bytes