Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 8a55c890a4d21dc8…

MALICIOUS

Office (OOXML)

178.5 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2021-06-20
MD5: 739a4e38973aca570e68c8f1a64f8ac0 SHA-1: c563ea88792aa7d12cf4cfc8ea33f9a4494f95ed SHA-256: 8a55c890a4d21dc8ed3a6875419f45d6e9d3d96ae8addf87855a6758da2bc5b3
182 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, indicated by critical heuristic firings for XLM_MACROSHEET, XLM_AUTOOPEN_DEFINEDNAME, and XLM_DANGEROUS_FN. The macros utilize dangerous functions like EXEC and FORMULA to call external Win32 APIs. The document body and extracted URLs suggest the macro's purpose is to download and execute a second-stage payload from the URLs https://keema.tk/SrJfCix7DHn/zv and https://birliklpgotogaz.com/05JQwseTb/zv.

Heuristics 4

  • 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, WORKBOOK.HIDE, 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.
  • 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://keema.tk/SrJfCix7DHn/zv In document text (OOXML body / shared strings)
    • https://birliklpgotogaz.com/05JQwseTb/zvIn 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 208741 bytes
SHA-256: baf5eb0d54f53574f5b47e6a6aadd3e3e7e3d7ffc3b25f5c7226b5a9ce7ae7e8
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="A1:BV283"/><sheetViews><sheetView showFormulas="1" zoomScaleNormal="100" workbookViewId="0"/></sheetViews><sheetFormatPr defaultColWidth="4.28515625" defaultRowHeight="15" x14ac:dyDescent="0.25"/><cols><col min="1" max="39" width="4.28515625" style="2"/><col min="40" max="40" width="4.140625" style="2" customWidth="1"/><col min="41" max="52" width="4.28515625" style="2" hidden="1" customWidth="1"/><col min="53" max="16384" width="4.28515625" style="2"/></cols><sheetData><row r="1" spans="1:41" x14ac:dyDescent="0.25"><c r="A1" s="1"/><c r="B1" s="1"/><c r="C1" s="1"/><c r="D1" s="1"/><c r="E1" s="1"/><c r="F1" s="1"/><c r="G1" s="1"/><c r="H1" s="1"/><c r="I1" s="1"/><c r="J1" s="1"/><c r="K1" s="1"/><c r="L1" s="1"/><c r="M1" s="1"/><c r="N1" s="1"/><c r="O1" s="1"/><c r="P1" s="1"/><c r="Q1" s="1"/><c r="R1" s="1"/><c r="S1" s="1"/><c r="T1" s="1"/><c r="U1" s="1"/><c r="V1" s="1"/><c r="W1" s="1"/><c r="X1" s="1"/><c r="Y1" s="1"/><c r="Z1" s="1"/><c r="AA1" s="1"/><c r="AB1" s="1"/><c r="AC1" s="1"/><c r="AD1" s="1"/><c r="AE1" s="1"/><c r="AF1" s="1"/><c r="AG1" s="1"/><c r="AH1" s="1"/><c r="AI1" s="1"/><c r="AJ1" s="1"/></row><row r="2" spans="1:41" x14ac:dyDescent="0.25"><c r="A2" s="1"/><c r="B2" s="1"/><c r="C2" s="1"/><c r="D2" s="1"/><c r="E2" s="1"/><c r="F2" s="1"/><c r="G2" s="1"/><c r="H2" s="1"/><c r="I2" s="1"/><c r="J2" s="1"/><c r="K2" s="1"/><c r="L2" s="1"/><c r="M2" s="1"/><c r="N2" s="1"/><c r="O2" s="1"/><c r="P2" s="1"/><c r="Q2" s="1"/><c r="R2" s="1"/><c r="S2" s="1"/><c r="T2" s="1"/><c r="U2" s="1"/><c r="V2" s="1"/><c r="W2" s="1"/><c r="X2" s="1"/><c r="Y2" s="1"/><c r="Z2" s="1"/><c r="AA2" s="1"/><c r="AB2" s="1"/><c r="AC2" s="1"/><c r="AD2" s="1"/><c r="AE2" s="1"/><c r="AF2" s="1"/><c r="AG2" s="1"/><c r="AH2" s="1"/><c r="AI2" s="1"/><c r="AJ2" s="1"/></row><row r="3" spans="1:41" x14ac:dyDescent="0.25"><c r="A3" s="1"/><c r="B3" s="1"/><c r="C3" s="1"/><c r="D3" s="1"/><c r="E3" s="1"/><c r="F3" s="1"/><c r="G3" s="1"/><c r="H3" s="1"/><c r="I3" s="1"/><c r="J3" s="1"/><c r="K3" s="1"/><c r="L3" s="1"/><c r="M3" s="1"/><c r="N3" s="1"/><c r="O3" s="1"/><c r="P3" s="1"/><c r="Q3" s="1"/><c r="R3" s="1"/><c r="S3" s="1"/><c r="T3" s="1"/><c r="U3" s="1"/><c r="V3" s="1"/><c r="W3" s="1"/><c r="X3" s="1"/><c r="Y3" s="1"/><c r="Z3" s="1"/><c r="AA3" s="1"/><c r="AB3" s="1"/><c r="AC3" s="1"/><c r="AD3" s="1"/><c r="AE3" s="1"/><c r="AF3" s="1"/><c r="AG3" s="1"/></row><row r="4" spans="1:41" x14ac:dyDescent="0.25"><c r="A4" s="1"/><c r="B4" s="1"/><c r="C4" s="1"/><c r="D4" s="1"/><c r="E4" s="1"/><c r="F4" s="1"/><c r="G4" s="1"/><c r="H4" s="1"/><c r="I4" s="1"/><c r="J4" s="1"/><c r="K4" s="1"/><c r="L4" s="1"/><c r="M4" s="1"/><c r="N4" s="1"/><c r="O4" s="1"/><c r="P4" s="1"/><c r="Q4" s="1"/><c r="R4" s="1"/><c r="S4" s="1"/><c r="T4" s="1"/><c r="U4" s="1"/><c r="V4" s="1"/><c r="W4" s="1"/><c r="X4" s="1"/><c r="Y4" s="1"/><c r="Z4" s="1"/><c r="AA4" s="1"/><c r="AB4" s="1"/><c r="AC4" s="1"/><c r="AD4" s="1"/><c r="AE4" s="1"/><c r="AF4" s="1"/><c r="AG4" s="1"/></row><row r="5" spans="1:41" x14ac:dyDescent="0.25"><c r="A5" s="1"/><c r="B5" s="1"/><c r="C5" s="1"/><c r="D5" s="1"/><c r="E5" s="1"/><c r="F5" s="1"/><c r="G5" s="1"/><c r="H5" s="1"/><c r="I5" s="1"
... (truncated)