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

Static analysis result for SHA-256 99cddee4c4ea4890…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: b02f0a0707874b14185ea66087efc936 SHA-1: 60c9647f5bcea8a225a78760b37b2dadad028dc7 SHA-256: 99cddee4c4ea48901759ccb56cf6b1946b91ce958d31993aab6a97fbb073264c
160 Risk Score

Malware Insights

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

The sample contains Excel 4.0 macros, specifically an Auto_Open function that utilizes dangerous APIs like RUN. This indicates the macro is designed to execute arbitrary commands. The presence of embedded URLs suggests the macro's primary purpose is to download and execute a second-stage payload. The ClamAV detection name 'Doc.Downloader.Docusign0521-9864805-0' further supports this downloader functionality.

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 http://me48.ru/ds/231120.gif
    • http://me48.ru/ds/231120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
b1a92fcba2ebe2fa90d2bd7eccdde9a9cc031a83a8bf04784dc2cdcfbba2a01a
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6292 bytes