IcedID — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 58f7b0c31ea1d8a2…

MALICIOUS

Office (OOXML) / .XLSM

173.8 KB Created: 2015-06-05 18:19:34 UTC Authoring application: Microsoft Excel 16.0300
MD5: 37924a04c4208d5bfdd3e022c5c53786 SHA-1: a5a77a3872a9ed047277035b1430cde1f126ea52 SHA-256: 58f7b0c31ea1d8a291b7efceef129974c62f3fa0bacb8d360575bf71afe73486
268 Risk Score

Malware Insights

IcedID · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1059.001 PowerShell T1204.002 Malicious File T1105 Ingress Tool Transfer

This XLSM file contains Excel 4.0 macros, which are known to be used for malicious purposes. The critical heuristic 'OOXML_XLM_DANGEROUS_FN' indicates the use of dangerous XLM functions like EXEC and REGISTER, commonly employed to download and execute payloads. The presence of an Auto_Open macro further suggests immediate execution upon opening. The ClamAV detection as 'Xls.Downloader.IcedID' strongly points to the IcedID family, a known downloader. The extracted URLs are highly suspicious and likely serve as the source for the second-stage payload.

Heuristics 8

  • Excel 4.0 macro sheet (3 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.
  • Dangerous XLM formula APIs: FORMULA, REGISTER, EXEC, 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
  • Auto_Open macro high OLE_VBA_AUTO
    Auto_Open macro
  • VBA project inside OOXML medium OOXML_VBA
    Document contains vbaProject.bin — VBA macros present
  • Suspicious extracted artifact medium EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET
    Excel workbook contains 3 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://45.150.67.244/44285,5327891204.dat
    • http://195.123.210.248/44285,5327891204.dat
    • http://91.211.91.69/44285,5327891204.dat
    • http://45.150.67.244/
    • http://195.123.210.248/
    • http://91.211.91.69/
    • http://schemas.openxmlformats.org/spreadsheetml/2006/main
    • http://schemas.microsoft.com/office/excel/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/spreadsheetml/2016/revision6

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
2f26ac96bba202e05dcf847261e1d1663d430574538bb7b407a117ed8f397467
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 727 bytes
vbaProject_00.bin
0de4024631c53d9eb47dbcdea5b13499fda054ab40208b596b6f142f38fda5c3
vba-project OOXML VBA project: xl/vbaProject.bin 10240 bytes
xlm_sheet_00.xml
80d1a34c6bae3f8d672561997f5de98fd384535946dcda1d571604f67feaa8ba
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 3871 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 shell/COM execution token(s).
xlm_sheet_01.xml
de9a94a6a839b1468572aebbbe877009c458e067a032a9d5fb0d49f065cce601
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet2.xml 1511 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 shell/COM execution token(s).
xlm_sheet_02.xml
7bc55721481c93f5e2dea31cdb217e35fe6802807e720b778603a24c7aa4ca5a
xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet3.xml 1506 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 shell/COM execution token(s).