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

Static analysis result for SHA-256 40bdd7a382128c61…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 8455d1430827c9459d06303dd41e0ef9 SHA-1: 3c1d2d84dfdea4de8d38da062eb0e262ab378725 SHA-256: 40bdd7a382128c617dcc882cc563f3b434eb18d6602cdd125ed950bb9e0bcf99
160 Risk Score

Malware Insights

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

The sample is an Excel file containing Excel 4.0 macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The SC_STR_SHELLEXEC heuristic suggests the macro uses ShellExecute to run external commands. The embedded URL points to a GIF file, which is likely a lure for a downloader. The ClamAV detection further confirms its malicious nature. The macro's intent is to download and execute a second-stage payload.

Heuristics 5

  • ClamAV: Doc.Downloader.Docusign0521-9864805-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Docusign0521-9864805-0
  • 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.
  • 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://tured.net/ds/261120.gif
    • https://tured.net/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
4805caad40efa88359221773489543a181039fb59e7111454d99230bce3bd306
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6674 bytes