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

Static analysis result for SHA-256 30f9d040a73df0f9…

MALICIOUS

Office (OLE) / .XLS

46.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-08
MD5: d328729be3f4d134de54ebaa3752e157 SHA-1: 81de9758e40dc957fecc74b6615ec52d477eec85 SHA-256: 30f9d040a73df0f937a088de32e12b91ec4a1af8c053d19eff2722993e3aa06d
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Service Execution: Service Control T1059.001 Command and Scripting Interpreter: PowerShell T1204.002 Malicious Link: Malicious File

The critical heuristic OLE_XLM_DANGEROUS_FN indicates the presence of dangerous Excel 4.0 macro functions, specifically the RUN function within an Auto_Open macro. This strongly suggests the macro is designed to execute arbitrary commands. The extracted URLs are likely destinations for downloading and executing a second-stage payload. The macro's intent is to download and execute a payload from one of the provided URLs.

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.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
f02d63843d495ffd8e99f1b7fe5f87a80501a758c9a61d8585f8be9700f36cb3
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7798 bytes