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

Static analysis result for SHA-256 1e5918db3c294afd…

MALICIOUS

Office (OLE) / .XLS

70.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-03
MD5: 0eed70018df2e7a2a54d8a3be44a22ba SHA-1: 175adba2c0f97e16ae3d9dbcf14eea6ec40b3cf9 SHA-256: 1e5918db3c294afd4b39c84d52a7819c790d590e9b7c1056b5d49154c8a538c5
140 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, specifically an Auto_Open function, which is a critical indicator of malicious intent. The macro sheet contains references to dangerous functions like RUN, suggesting it is designed to execute arbitrary commands. The extracted URLs are likely used to download and execute a second-stage payload. The presence of the Auto_Open function and the use of dangerous APIs strongly indicate a malicious downloader.

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
b2124f09a0fec7faeef42f88c68da164b6a9b84efed16f528c7ac11c7695b4b9
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7646 bytes