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

Static analysis result for SHA-256 c77551e02bc43607…

MALICIOUS

Office (OLE) / .XLSX

76.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: ae8ecff18b0e793dff0678725c6feebd SHA-1: 57a61dc961c8e0fed09e8742a7f0dd382e20b531 SHA-256: c77551e02bc43607ccfb6abdbbfaf1ba1aecfcdfb4e8c9091595b4ba1b8dba2b
120 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.005 Visual Basic T1218.011 Rundll32

The sample contains Excel 4.0 macros with an Auto_Open entry, indicating it's designed to execute automatically upon opening. The document body impersonates DocuSign and instructs the user to enable macros, a common lure. The extracted macro code contains calls to rundll32 with DllRegisterServer and RLDownloadToFileA, suggesting it downloads and executes a second-stage payload from one of the provided URLs. The specific URLs are: giftcard16.com/ozdomsmm/, www.ausfencing.org/pafmwptlztwo/, mubasharhussain.ml/lwjiel/, artisthub.farahasmar.com/bzdydzj/, and rrmmarketing.com/qqduill/.

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