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

Static analysis result for SHA-256 12f9f1cac3da80db…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 6f9fdb2672c12e1f627c42d9dae501d3 SHA-1: a4411123158ad3b902ae8b51fc805158d6a64daf SHA-256: 12f9f1cac3da80dbdb1d5dbceb18fabbd5191648a09aa6bc983bbc2351ef088b
242 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1566.001 Spearphishing Attachment

The file contains Excel 4.0 macros with an Auto_Open entry, which is a critical finding indicating automatic execution upon opening. The macros utilize the RUN function and a CALL to ShellExecute API, with one entry explicitly referencing the URL https://avra.dtmh.gr/ds/231120.gif. This suggests the macro is designed to download and execute a second-stage payload from this URL, aligning with a downloader pattern.

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://avra.dtmh.gr/ds/231120.gif
    • https://avra.dtmh.gr/ds/231120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
8b13557c7c753c9d978b32b1134fab6c924344fc591b06bd0cf8f75d5ca380b6
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6060 bytes