Office (OOXML) / .XLSM malware analysis — malicious · 81ed52b626768394

MALICIOUS

Office (OOXML) / .XLSM

76.6 KB Created: 2020-04-01 21:52:48 UTC Authoring application: Microsoft Excel 14.0300

MD5: 9f8f23acbdff14fe398ebb205403186b SHA-1: 2e16a1559c43482fb90c033f50f06547a708cc85 SHA-256: 81ed52b62676839441041e6606d9a8dcf7598e885337b5247c69d4afcc3abccf

210 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file is an XLSM document containing multiple Excel 4.0 macro sheets. Heuristics indicate the use of dangerous functions like RUN and CALL, which are commonly used to download and execute payloads. The presence of embedded URLs suggests a download-and-execute attack pattern. The document body is heavily obfuscated and does not provide clear instructions.

Heuristics 6

Excel 4.0 macro sheet (11 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: RUN, CALL, 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.
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 11 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 https://addledsteamb.xyz/BAYgODA0NUQ2OEY1RTA2ODg4RDhCQzlEQzRBRUU3QTA5OUI=
- https://addledsteamb.xyz/BAYg
- 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 3

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`xlm_sheet_00.xml` `ec6fb1620b7920ba485f10765250e928647f3aafa797249bab04a3ffd5ab4890`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet4.xml	716 bytes
`xlm_sheet_02.xml` `477442b9bf77bd0488297eb6385fd7b523654f96465568cc9d5604f9bb575e05`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet2.xml	30523 bytes
`xlm_sheet_03.xml` `308c0fee671459705221c5f1a8cee944f5ea803fddd0faa620cc8266d48c662b`	xlm-macrosheet	OOXML XLM macro sheet: xl/macrosheets/sheet1.xml	74887 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 3 shell/COM execution token(s).

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