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

Static analysis result for SHA-256 1e2c8ebf40d41021…

MALICIOUS

Office (OLE) / .XLS

67.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-05-20
MD5: 06f5b0abbdbc2f81e68ead7782176ee1 SHA-1: 4408e9220b0a5e88f5e190958ed70c45f965d2a3 SHA-256: 1e2c8ebf40d4102193dd68bcfecc15dee112321c579e9bf88bac19a13f1f8ce3
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Service Execution: Service Execution T1059.001 PowerShell: PowerShell T1204.002 Malicious File: Malicious File

The critical heuristics OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN indicate the presence of Excel 4.0 macros with an Auto_Open entry, which is a known technique for executing malicious code. The extracted URLs are highly suspicious and likely serve as download locations for secondary payloads. The macro's intent is to download and execute a payload from one of these URLs.

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