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

Static analysis result for SHA-256 cc9e16e2538f4ca7…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 63b351c0a686accca083623fc73b335c SHA-1: 18be1b18f2206b5fb9924853d0e74812b46e6e4d SHA-256: cc9e16e2538f4ca774dfa49eee2469bd2840d2ac91a5d3daaa61d19ec427f6a4
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File T1059.001 PowerShell T1105 Ingress Tool Transfer

The sample contains Excel 4.0 macros, specifically triggering an Auto_Open event with dangerous functions like RUN. This indicates the macro is designed to execute arbitrary commands. The presence of an embedded URL suggests the macro's purpose is to download and execute a second-stage payload. The ClamAV detection name 'Doc.Downloader' further supports this assessment.

Heuristics 5

  • 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
  • XLM Auto_Open with dangerous formula APIs high 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.
  • 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://ctxpress.com/ds/261120.gif
    • https://ctxpress.com/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
aa837a287543a9593dc9ad53c5a1043539349d9d7158b9d02f92e2bb7330dc0f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6677 bytes