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

Static analysis result for SHA-256 101232804990faf8…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 79afef4b82f3d7a20f10d7e19b2006e1 SHA-1: f75231055ea93fee830d82273ac23cec42d959de SHA-256: 101232804990faf89326214f4cf002495713d04619c5c3258a638f62a0f1bb9a
242 Risk Score

Malware Insights

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

The sample contains Excel 4.0 macros that are configured to automatically execute upon opening, indicated by the Auto_Open defined name. These macros utilize the RUN function and a CALL function to execute code, likely to download and execute a second-stage payload from the embedded URL 'https://avra.dtmh.gr/ds/231120.gif'. The use of ShellExecute API further supports the execution of external commands.

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