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

Static analysis result for SHA-256 812961c7818a3b85…

MALICIOUS

Office (OLE) / .XLS

180.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 6e091a23d18d86d48f4e292b05cc5a22 SHA-1: 461e355b7510705f0d0886e77641ce608392dac6 SHA-256: 812961c7818a3b8532bdb1f3d85a3420721635db1093d3ee49dbd43013e0bc85
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample contains Excel 4.0 macros, including an Auto_Open function, which is a known technique for executing malicious code. The macros are designed to bypass security warnings by instructing the user to enable content. The script attempts to download a payload from several URLs, including http://vts.us.com/ds/0104., http://mundotecnologiasolar.com/ds/0104., http://accesslinksgroup.com/ds/0104., http://ponchokhana.com/ds/0104., and http://comosairdoburaco.com.br/ds/0104., indicating a downloader or droppper functionality.

Heuristics 4

  • 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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
917baaae0e48794e5eb73ae3d5cf93c43110b97da5df3e45bc2f236b5551c875
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 27158 bytes