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

Static analysis result for SHA-256 4403e7ba0dff3d60…

MALICIOUS

Office (OLE) / .XLSX

274.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel First seen: 2022-09-22
MD5: f84bc22a860f9fb35c572fb1c637cbb7 SHA-1: 9f9571a2d4cf3be93c1f91100ce9f19072ee584a SHA-256: 4403e7ba0dff3d601017cea64af7025b24fa23cc6a3f60da80984ddc2188d753
120 Risk Score

Malware Insights

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

The sample contains Excel 4.0 macros, including an Auto_Open entry, which is a strong indicator of malicious intent. The document body contains a lure impersonating a document signing service and a URL that likely serves as a download location for a second-stage payload. The presence of the Auto_Open macro and the embedded URL strongly suggest this file is a downloader for further malicious activity.

Heuristics 4

  • 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.
  • 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
  • Document signing service impersonation lure medium SE_DOCUSIGN_LURE
    Document impersonates DocuSign, Adobe Sign, or a similar signing service in a signing-request context

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
2acc40593deff0c34d67182765876672f026f8c9c5e7440b3c57c2eef485a4a2
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3778 bytes