Trickbot — Office (OOXML) / .XLSM malware analysis

Static analysis result for SHA-256 c5d88e77f9c56fbd…

MALICIOUS

Office (OOXML) / .XLSM

92.4 KB Created: 2006-09-16 00:00:00 UTC Authoring application: Microsoft Excel 14.0300
MD5: dffc033b7320f999634cd5c222937e46 SHA-1: 6668e4aab04a2a8928afff47b82064eababa4392 SHA-256: c5d88e77f9c56fbd48a925aa50a425f47a11c2f216d4930c03ce7eadcbd57e29
240 Risk Score

Malware Insights

Trickbot · confidence 95%

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

This XLSM file contains Excel 4.0 macros, including an Auto_Open defined name, which is a common technique for initial execution. The macros utilize dangerous functions like CALL and EXEC to download and execute a second-stage payload from the URL http://living-traditions.com/blogs/click.php. ClamAV detection further confirms this as a Trickbot downloader variant.

Heuristics 5

  • 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.
  • 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: HALT, CALL, EXEC 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.Trickbot07210-9880007-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Trickbot07210-9880007-0
  • 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://living-traditions.com/blogs/click.php
    • 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

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
emf_00.emf
ab58818ae1864807b22f8a58a75f7fa8703ecb19a2352bdb47469f366b868e59		 ooxml-emf OOXML EMF part: xl/media/image1.emf 1108 bytes
xlm_sheet_00.xml
e4b281892d0ea349b67e22f5137ff45445837a231636a77def5d03453653a180		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet3.xml 1320 bytes
xlm_sheet_01.xml
dc6f94d6a4ba861acb967e43bffdd40434a4af702aa49fecd339a534a914cf25		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet2.xml 1296 bytes
xlm_sheet_02.xml
8faff306084010389946628f47b22e9cb5995393bc56355b17f2d18c3fd7944c		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/intlsheet1.xml 1246 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.