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

Static analysis result for SHA-256 8ee305eec94aaef2…

MALICIOUS

Office (OLE) / .XLSX

261.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: a7c64329efaea29a2dc97ced238490f7 SHA-1: 5d4b9b386354444cf74fd858e3409f0294c45330 SHA-256: 8ee305eec94aaef24116983ceef933359fb860ab50787b7963c3f46fe751630c
120 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 User Execution: Malicious File T1059.005 PowerShell

The sample contains Excel 4.0 macros with an Auto_Open entry, a common technique for executing malicious code upon opening. The document body and heuristics indicate a lure to impersonate a document signing service (DocuSign) to trick the user into enabling macros. The presence of 'rundll32' and a suspicious URL suggests the macro is intended to download and execute a second-stage payload.

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
1cce783a487c585d0f0d553a6dcc92b7a1cc8611def516623538f51ccff16f05
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 4427 bytes