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

Static analysis result for SHA-256 9c165dd05ca0db19…

MALICIOUS

Office (OLE) / .XLS

67.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-05-20
MD5: 41c5c01b0e9dc3cfdcb6455d7cdac79c SHA-1: 9a5e5d5df65efab1ca0bbca61778fb1edd158ca0 SHA-256: 9c165dd05ca0db194bf5874252214170b5c95268101df9bd0e112246dfe93737
140 Risk Score

Malware Insights

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

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open function, which is a known technique for executing malicious code. The macro attempts to download a second-stage payload by concatenating strings to form multiple URLs. The reconstructed URLs are: "https://www.melisetotoauksuar.com/catalog/controller/account/dqfKI/", "http://elmurray.com/athletics-carnival-2018/3UTZYr9D9f/", "http://masyuk.com/581voyze/MlX/", and "http://j-software-web.net/aabackupsqldb/11hYk3bHJ/". This indicates a downloader or droppper functionality.

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
67f6b164c4d6ea1ea8efe2ccdff056dde7fd1072da2bb20afe3b275864086c71		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7678 bytes

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