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

Static analysis result for SHA-256 6af2e6c3755873fe…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 0bfea9817c89d2e3304eaf242a7fd113 SHA-1: e3b1efeeaa1d3001c35ffefa7aebff91533d97a8 SHA-256: 6af2e6c3755873fe46d6df3e3d364406b0fc57cbea84c016bc209fe8d46b2145
242 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros that are configured to auto-execute upon opening. These macros utilize the RUN and CALL functions to execute code and reference external URLs, specifically 'https://zerones.biz/ds/261120.gif'. The presence of ShellExecute API calls and dangerous formula APIs like RUN indicates a downloader or execution mechanism. The macro's complex CALL function suggests it's attempting to construct and execute a command, likely to fetch and run a second-stage payload.

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://zerones.biz/ds/261120.gif
    • https://zerones.biz/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
7fbdfe5319125c7a88728c7d99286583a9907fcc6c0161898412d727b081f128
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6676 bytes