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

Static analysis result for SHA-256 5792591327b92c65…

MALICIOUS

Office (OLE) / .XLS

70.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-07
MD5: 0bd818ec1abd78a38f1168bcdc225521 SHA-1: 15c384c46a3c4aa80e27def61f6d50d496af1536 SHA-256: 5792591327b92c6577e784aa91a15868fbfd02fdd60bdedc671a18a775009905
140 Risk Score

Malware Insights

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

The critical heuristics OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN indicate the presence of an Excel 4.0 Auto_Open macro that uses dangerous functions like RUN. The macro sheet contains concatenated strings that reconstruct multiple URLs, likely intended for downloading and executing a second-stage payload. The specific URLs identified are the highest priority IOCs.

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
b4f0a647cf6176132ebc9ecde0dbe63bae14d0fc3c1b3805926fc56fef0b0f6a		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7650 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.