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

Static analysis result for SHA-256 d2c82d948b2a60a7…

MALICIOUS

Office (OLE) / .XLSX

145.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: 60ae3df7ad2558afe04a77dee5ded712 SHA-1: 453ccf4131c9c433f6c3b68a3fce7621e0638d15 SHA-256: d2c82d948b2a60a7bcf6633e73bcfb48d961bee77d0fd22a1a6aff968eac58bb
262 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 macro, which is a critical indicator of malicious intent. These macros are designed to reconstruct and execute URLs, as evidenced by the reconstructed strings in the DOC BODY section. The primary function appears to be downloading and executing a second-stage payload from one of the five provided URLs. ClamAV also detected this as Doc.Downloader.EmotetRed02222-9938635-0, further supporting its malicious nature.

Heuristics 6

  • 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.
  • URL reconstructed from XLM cell array (5 URLs) critical OLE_XLM_CELL_ARRAY_URL
    Excel 4.0 macro sheet stages its payload URL across the BIFF8 Shared String Table (one quoted-char SST entry concatenated with & at runtime) or across individual numeric cells (one ASCII charcode per cell). The reconstructed URL is invisible to literal-bytes URL extraction because it is never contiguous in the workbook stream. URLs were recovered by walking the BIFF8 record stream and decoding SST entries plus LABELSST/RK/NUMBER cells.
  • ClamAV: Doc.Downloader.EmotetRed02222-9938635-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetRed02222-9938635-0
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://lupus.ktcatl.com/wp-content/uCccWJ/
    • https://packersandmoversbangalorecharges.com/cgi-bin/UrI6GM87K5u2y2pOW/
    • http://123breathe.org/error/Drs/
    • https://greenesqualityflooring.com/error/kUO7NnkpMp2cs/
    • http://new.hssus.org/wp-includes/blocks/eKID0QAfLUS/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
1574ee13450fd34682012e2ebea7c020d326605272204fb688e7873d4a7c8165		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6756 bytes

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