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

Static analysis result for SHA-256 147db9bb2e91f90b…

MALICIOUS

Office (OLE) / .XLS

229.0 KB Created: 2020-09-20 21:17:44
MD5: f4e43143060e196496985875d896eb93 SHA-1: 6a37e313d24873f0ffdaf0d9ac0f316905466b21 SHA-256: 147db9bb2e91f90b5ccd250e8aba552fe9a3cc5bac4d28b761fe3af3bf3987d0
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1566.001 Spearphishing Attachment

The Excel 4.0 macro sheet contains an Auto_Open macro that uses the EXEC function to run a PowerShell command. This command is designed to download a file named 'pd.bat' from the URL https://cutt.ly/ijaxK0R into the temporary directory and then execute it. The macro also includes commands to hide and execute the downloaded batch file.

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
000a864e6c51d47f41fe7bceb92c4da87f8b0813d9bf6ade2d57c66bdd727856
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 1484 bytes