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

Static analysis result for SHA-256 ce9e8c29596fb727…

MALICIOUS

Office (OLE) / .XLS

46.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-14
MD5: 6b2adc1da95f6cab2659df475a8ee8c3 SHA-1: fc3d132bd0c3dd2db3864a5be82141357d4808c6 SHA-256: ce9e8c29596fb727e1a414b1c38cd00d53f5253cdf706c1a26ed0a9c0244a970
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File

The file is an Excel 4.0 macro-enabled spreadsheet containing an Auto_Open function, which is a critical indicator of malicious intent. The macro sheet contains references to dangerous functions such as RUN, suggesting it is designed to execute arbitrary code. The extracted URLs are likely used to download and execute a second-stage payload. The confidence is high due to the presence of the Auto_Open macro and the explicit use of the RUN function.

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