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

Static analysis result for SHA-256 af4a19fee4fc1f71…

MALICIOUS

Office (OLE) / .XLS

373.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 3807dc2f0f647228dde815b0d95db38d SHA-1: 381509d7263acbdfecf909f24b6704e3b7fcaffd SHA-256: af4a19fee4fc1f71e357f9d53c118ef576a84ebe5441a39a32271d93e15ab157
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. It contains an Auto_Open macro that uses dangerous functions, indicating an attempt to execute arbitrary code. The document also contains a lure to enable macros, a common technique for malware delivery. The extracted URLs likely host the secondary payload.

Heuristics 5

  • 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.
  • 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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • 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://techserve4u.com/utlqwePl9XKr/alex.html
    • https://evershinesoftware.com/isei5Q7KlsQ5/alex.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
599707db4356dee9b1659b3a18ea6968bd26a6e750ede458308d788c900c5e21
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 5292 bytes