Office (OOXML) / .XLSM malware analysis — malicious · 5b04afff395a8c35

MALICIOUS

Office (OOXML) / .XLSM

109.5 KB Created: 2006-09-16 00:00:00 UTC Authoring application: Microsoft Excel 14.0300

MD5: 3ba31c124b879cb7d15f638553fd8981 SHA-1: 7217e7803e963c9400a6a29a8c4270b9eb742a37 SHA-256: 5b04afff395a8c350a6b2bd2de02646486c6f7fd0af5f5d1c685a04b3728c313

210 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1204.002 Malicious File

The sample contains critical heuristics indicating the presence of Excel 4.0 macros, including the use of dangerous functions like EXEC and CALL. These macros are designed to download and execute a second-stage payload from the URLs provided in the document body and within the macro code itself. The use of EXEC with arguments like '..\duron.bnm1' and '..\duron.bnm2' suggests an attempt to execute malicious binaries.

Heuristics 6

Excel 4.0 macro sheet (2 sheet(s)) critical OOXML_XLM_MACROSHEET

Spreadsheet contains an Excel 4.0 (XLM) macro sheet — XLM was a major Office malware vector during 2020-2022 and evaded many VBA-focused controls before Microsoft tightened XLM defaults. Even legitimate XLM use is rare in modern workbooks.
Excel 4.0 Auto_Open defined name critical OOXML_XLM_AUTOOPEN_DEFINEDNAME

Workbook defines _xlnm.Auto_Open or _xlnm.Auto_Close while containing an XLM macro sheet. This is the OOXML/XLSB auto-execution shape for Excel 4.0 macros.
Dangerous XLM formula APIs: EXEC, HALT, FORMULA, WORKBOOK.HIDE, CALL critical OOXML_XLM_DANGEROUS_FN

Excel 4.0 macro sheet uses formula APIs that call directly into Win32 (=CALL/=EXEC/=REGISTER/=FORMULA). These are the primitives used to download payloads, write files, and start processes from an XLM macro without invoking VBA.
Suspicious extracted artifact medium EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET

Excel workbook contains 1 hidden sheet(s) — hidden sheets are commonly used to conceal macro code, staging data, or intermediate payload construction
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 https://immobiliareneri.casa/drms/ind.html
- https://gidbasket.com/drms/ind.html
- http://schemas.openxmlformats.org/spreadsheetml/2006/main
- http://schemas.microsoft.com/office/excel/2006/main
- http://schemas.openxmlformats.org/officeDocument/2006/relationships
- http://schemas.openxmlformats.org/markup-compatibility/2006
- http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac

Extracted artifacts 2

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`xlm_sheet_00.xml` `7d118572f5fe7d6ff43ed02ebd45ba65e8abef406e7a780baf6c364273fc6add`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/intlsheet2.xml	3454 bytes
`xlm_sheet_01.xml` `fbe5e7dbb69c9673a292262e360301ab1ec7a303eb74e3af592196e67c71385f`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml	205673 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 2 shell/COM execution token(s).

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