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

Static analysis result for SHA-256 378f404274049990…

MALICIOUS

Office (OLE) / .XLS

142.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: aa1b2bdb5a705f127662601598408d07 SHA-1: ea76be5967dc202b6a2f0dd7b1ded3e0dd0b2ccc SHA-256: 378f404274049990ae84612d42307b2bcfb27862357a28e4c707e33667516c46
160 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, specifically an Auto_Open function, which is a critical finding. The macro sheet includes a dangerous formula API call (RUN=0), indicating it's designed to execute code. The presence of a 'Macro/content-enable lure' heuristic suggests the document attempts to trick the user into enabling macros. The extracted DOC BODY content and embedded artifacts point towards a downloader attempting to fetch a payload from the URL 'lxoyw10bipu03ilyig.com/index.'.

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
35abf0a61b6cc7d0d67bd7de5baddeefdc7aabb3b44425155a6b39f4cd91b879
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6360 bytes