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

Static analysis result for SHA-256 11b5cd4cee155e04…

MALICIOUS

Office (OLE) / .XLS

34.0 KB Created: 2020-12-02 14:02:33 Authoring application: Microsoft Excel
MD5: 5c89c847c7272b5739e282ce28e82a44 SHA-1: 096fb188ebf9f6ce0ad71d3ad0006a5c51f48b97 SHA-256: 11b5cd4cee155e041a201435af76630b6e1529170ce5059a349dde79009c32c8
140 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open macro, which is a common technique for executing malicious code upon opening the document. The document body contains a lure to "Enable Editing" and "Enable Content", typical for macro-based attacks. No specific URLs or executable payloads were directly extracted, but the presence of an Auto_Open macro strongly suggests an attempt to execute arbitrary code.

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
0b5f95431b7ddba86819c480c8385fee18788e7f0056927528e34f7e195e86a5
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3389 bytes