IcedID — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 b7b1def00c077728…

MALICIOUS

Office (OOXML) / .XLSM

174.2 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300
MD5: 5953806465e8072d5f7c3579ed670bf0 SHA-1: bcb2587c6da991bd16449113644b8cb914f1c019 SHA-256: b7b1def00c0777288af4a56a9881ca52ef658e3a1f088b7a116ee8bed30c8d22
250 Risk Score

Malware Insights

IcedID · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File

This XLSM file contains multiple Excel 4.0 macro sheets, including an Auto_Open macro, which is a common technique for initial execution. The macros utilize dangerous functions like FORMULA, GOTO, and HALT to directly call Win32 APIs, enabling the download and execution of a second-stage payload. ClamAV identified the sample as Xls.Downloader.IcedID, suggesting this family.

Heuristics 6

  • Excel 4.0 macro sheet (6 sheet(s)) critical 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.
  • ClamAV: Xls.Downloader.IcedID-9f1f1d193a2a2a2b-9951463-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.IcedID-9f1f1d193a2a2a2b-9951463-0
  • 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 — context-specific rules above attribute URLs they actually evaluated; this rule lists URLs that were present in the bytes but were not otherwise tied to a specific finding.
    URL http://schemas.openxmlformats.org/spreadsheetml/2006/main
    • http://schemas.openxmlformats.org/officeDocument/2006/relationships
    • http://schemas.openxmlformats.org/markup-compatibility/2006
    • http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac
    • http://schemas.microsoft.com/office/spreadsheetml/2014/revision
    • http://schemas.microsoft.com/office/spreadsheetml/2015/revision2
    • http://schemas.microsoft.com/office/spreadsheetml/2016/revision3
    • http://schemas.microsoft.com/office/excel/2006/main
    • http://schemas.microsoft.com/office/spreadsheetml/2016/revision6

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml
e26278d9df62929caddc39c2675d1a93c805965a35896b4c4240468b728373e2
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 1190 bytes
xlm_sheet_01.xml
b0c92abb60a2275195a7039b8d0c793da46292b6cf2282abe16347418f199576
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet2.xml 3195 bytes
xlm_sheet_02.xml
60860e3e942fc249672c3f297fa7f4b06db5f5d49d084784eafb2c3e4889ad39
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet3.xml 2298 bytes
xlm_sheet_03.xml
f6023b616a33da16850bd04bca335ab61b8bf9717cbe0a8ef91527cea67ae7fd
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet4.xml 2025 bytes
xlm_sheet_04.xml
d60ca3a864e3f818e7a00f9aa3f6fdbc180e13ef9ef26c0d3de35bf633fcfa97
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet5.xml 1560 bytes
xlm_sheet_05.xml
dd9efeb7c324f68d06e9a7e99610df77ef935e2fc86a64fc3a473904f7bcfe45
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 1821 bytes