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

Static analysis result for SHA-256 0a12f7277bba2bfe…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 3994c6ff9e2debe1354f0c54e5be46aa SHA-1: fd06e10eb0984827eb7f1308e228b7e23c82a0ad SHA-256: 0a12f7277bba2bfeb220b205767acdbe2e467ebc6618c09b8f60c7b092b30421
242 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The sample contains Excel 4.0 macros with an Auto_Open entry, indicating automatic execution upon opening. Heuristics indicate the use of dangerous functions like RUN and CALL, suggesting the execution of a secondary payload. The macros attempt to construct and execute commands that include external URLs, such as 'https://5gict.com/ds/261120.gif', likely to download and run additional malicious content.

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.
  • 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
  • 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://5gict.com/ds/261120.gif
    • https://5gict.com/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
a172d04deb874bfc5428cadf9fe508e67386f425fa8a97e12d80c959c827f2d9
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6674 bytes