Malicious Office (OOXML) / .XLSM — malware analysis report

Static analysis result for SHA-256 1cbf2a3b6e588f54…

MALICIOUS

Office (OOXML) / .XLSM

432.4 KB Created: 2006-09-16 00:00:00 UTC Authoring application: Microsoft Excel 15.0300
MD5: e0c8c7a3c81d2939da195e9ec650065d SHA-1: 4d634a114cbdfcc0e289dee5026c99feb3ceac9c SHA-256: 1cbf2a3b6e588f54f873e9ce874f4081bd22a36384a408dba6924e870f83849b
100 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Service Execution: Service Control T1204.002 Malicious File: User Execution T1105 Ingress Tool Transfer

The sample is an XLSM file containing Excel 4.0 macros. These macros utilize dangerous API calls such as REGISTER and HALT, which are known primitives for downloading and executing payloads. The document body explicitly mentions downloading a file from the provided URL and executing it, indicating a downloader or droppper functionality. The confidence is high due to the direct evidence of macro usage for payload execution.

Heuristics 3

  • Dangerous XLM formula APIs: REGISTER, 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.
  • Excel 4.0 macro sheet (1 sheet(s)) high 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.
  • 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://213.252.247.207/hq-for/mem.exe

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_sheet_00.xml
63d89ea0723d5d561618f72c9d85e3de136bfdc37eb6ba3d640d078b9bc3ad76		 xlm-macrosheet OOXML XLM macro sheet: xl/macrosheets/sheet1.xml 1974544 bytes

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