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

Static analysis result for SHA-256 f6ff5f411f10b991…

MALICIOUS

Office (OLE) / .XLSX

76.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: 6ac1882d9a25ed027d07089fcd4682fc SHA-1: 8b78b85790005e7526e40ca0331f5a7addedca00 SHA-256: f6ff5f411f10b991c5a16e6b6417530966f46f06cb5c43c1245bda951184ee04
120 Risk Score

Malware Insights

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

The sample contains Excel 4.0 macros with an Auto_Open entry, indicating it will execute automatically when the workbook is opened. The document body impersonates DocuSign and instructs the user to enable macros, a common lure. The extracted URLs are likely used to download and execute a second-stage payload, potentially using rundll32.dllregisterserver or similar functions.

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
28583d80fd380b8ce44feed33486a243b72383f3879b4322afeadd5f9732c23b
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 2255 bytes