Emotet Office (OOXML) / .XLSM malware analysis — malicious · fc5b918630ca4c23

MALICIOUS

Office (OOXML) / .XLSM

46.5 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2022-03-03

MD5: c3a20a9e514b067e4c4f2de0dce25963 SHA-1: 018a5b5f1c9d19228886566f831518478b3e2640 SHA-256: fc5b918630ca4c231ce8320f6623d18f6e935993652cd56751cab3556eaa6220

250 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK

T1059.005 Service Execution: Visual Basic T1059.001 Command and Scripting Interpreter: PowerShell T1204.002 Malicious Link: Malicious File T1105 Ingress Tool Transfer

This XLSM file utilizes Excel 4.0 macros, specifically leveraging the dangerous FORMULA API, to download and execute a second-stage payload. The macros construct a command that includes 'regsvr32.exe' and a URL from which to download the payload. The ClamAV detection as 'Xls.Downloader.Emotet03220-9940726-0' strongly suggests the Emotet family. The embedded URLs are the primary indicators for the initial stage of the infection chain.

Heuristics 6

Excel 4.0 macro sheet (3 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: FORMULA 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.
ClamAV: Xls.Downloader.Emotet03220-9940726-0 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Xls.Downloader.Emotet03220-9940726-0
Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET

Excel workbook contains 5 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://goglobetravel.com/wp-admin/1O1Tjr9nHBV/
- http://nazrultheking.com/wp-includes/LZ/
- https://pakistannakliye.com/wp-admin/dyfAdRkv7/
- http://hossaibmojammel.com/wp-content/qFPghprWO0ONxLFA5d/
- https://spinoffyarnshop.com/content/YQlmbLaB/
- http://murtjizindustry.com/wp-content/yI6/
- 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
- http://schemas.microsoft.com/office/spreadsheetml/2014/revision
- http://schemas.microsoft.com/office/spreadsheetml/2015/revision2
- http://schemas.microsoft.com/office/spreadsheetml/2016/revision3
- http://schemas.microsoft.com/office/spreadsheetml/2016/revision6

Extracted artifacts 3

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`xlm_sheet_00.xml` `c2beed76b90707ab99d3556b095847fbe67565665bab2978d4d40d1b769c68e7`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml	4017 bytes
`xlm_sheet_01.xml` `3f1e04bcb932a0d7a0ca09ad6e05d398d7a144c4cda86314010c0ec3e9f94573`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.xml	1278 bytes
`xlm_sheet_02.xml` `3877aa64e871d2d6fcc766f5b3af64ba0d301f656023d2e6e43652b8210d827c`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet2.xml	1152 bytes

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