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

Static analysis result for SHA-256 189f9d16a00dfda9…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 634813a453be698690165e2302a1b03c SHA-1: 9e7ff2495d08d8f235dc1bc852c797646609a4fe SHA-256: 189f9d16a00dfda96791fde5e35ebce9cbbbb4647ff77af0326b7a902b2dd93f
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 it will execute automatically upon opening. The macros utilize the RUN function and CALL to execute Win32 API functions, specifically referencing 'kernel32.dll' and 'CreateA', likely to download and execute a second-stage payload from the embedded URL. The presence of the ShellExecute API reference further supports this malicious intent.

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