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

Static analysis result for SHA-256 07ed07a5b2471d76…

MALICIOUS

Office (OLE) / .XLS

70.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-05-28
MD5: df906f6852627319b26686239950b926 SHA-1: 11e483442fe3771dbda9f223d9f1253e6fe74617 SHA-256: 07ed07a5b2471d76295b5266553f307717282580485dd788d7a97ba3b0b5c234
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open entry point, which is a common technique for executing malicious code within older Excel versions. The extracted formulas, including calls to RUN, suggest the macro attempts to download and execute a payload from the provided URLs. The use of Auto_Open and the RUN function points to T1059.005 (Visual Basic) and T1203 (Exploitation for Client Execution).

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
699e21f010c7c5f5713063f52e691ec519f766e81393f8793f7a585cd43d5349
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7635 bytes