IcedID — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 345baf3102f5e8b3…

MALICIOUS

Office (OOXML) / .XLSM

344.3 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300
MD5: a4c193e81eebbbc3a92ac7f777eae207 SHA-1: 79a5a1f4604c745a48fcb488fc8362bcd8491122 SHA-256: 345baf3102f5e8b3ae5b9064d3f87802d136262ecc8307b550dd79f762e02ca4
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 defined name, which is a common technique for initial execution. The macros utilize dangerous functions like FORMULA, GOTO, and HALT, indicating an intent to download and execute a payload. The ClamAV detection explicitly identifies the file as an IcedID downloader, supporting this assessment.

Heuristics 6

  • Excel 4.0 macro sheet (14 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 14 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 14

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml
83dba5bfbe15006ac89e8f80dd7cef1659412a3734905e1c32eb8daf6ea654c1
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 1380 bytes
xlm_sheet_01.xml
c82a3f1a5a07e2c3dfdeeb07a65d6c60c5bde7fafc322a698567c77157ce96d2
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet2.xml 1616 bytes
xlm_sheet_02.xml
2d666c0156d5379ae66f25c08b3a2af99682820e2f3d34113e67d10adba7eb62
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet3.xml 2222 bytes
xlm_sheet_03.xml
9d8986bb062b9186e1a421018441d943a727ec73bb2986a952946ed6431b5278
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet4.xml 3698 bytes
xlm_sheet_04.xml
6b929601bfad3874005a5bda78c3b4c48ed44c0b86f6fd6b66e1ef3a9b1483ba
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet5.xml 2313 bytes
xlm_sheet_05.xml
d426f8d1ffb9f4cae0b3596b59264854211f5a37409aff811f2b6e3d0b4471fc
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet6.xml 1743 bytes
xlm_sheet_06.xml
7c938a7bb5e1d49c23f50c7382eb8d69094ccdb58d4425ca8ed1a35098f12ad9
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet7.xml 1740 bytes
xlm_sheet_07.xml
722e5d05ff76efbc613cfc8faf6010a45d36bce5b42c805efd4dad491ab57285
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 1585 bytes
xlm_sheet_08.xml
bbabdb72f964374a773f09d55c2ef66fa57494857b47c84f6883880468c3e05f
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet8.xml 1795 bytes
xlm_sheet_09.xml
ee656362086a167f40427380169b904c4e8f6d7223dba3711b5f2ca8ecae3067
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet9.xml 1879 bytes
xlm_sheet_10.xml
2166c7457651893fa9459576c7b181df82d76c4fcebd021c0c20c24dedc93e62
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet10.xml 1920 bytes
xlm_sheet_11.xml
d336d714c064b1de9e9a56ccd73ade8b1f0edff76c17a7e66d685ef714ea6d20
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet11.xml 1929 bytes
xlm_sheet_12.xml
aac2ffcbbae09ab4b5869d56560bc65d237d62e10fc10d91608ce8e2b370ca9d
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet12.xml 2195 bytes
xlm_sheet_13.xml
f132f4041e583271c3d5f2834d2cb24dbe90419bc9d67396179c90ec86cd5770
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.xml 1442 bytes