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

Static analysis result for SHA-256 5956a0a7da895b92…

MALICIOUS

Office (OOXML) / .DOC

3.37 MB Created: 2022-07-26 00:59:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2022-07-27
MD5: 68e8afb2d86bbbb577387d87290b406c SHA-1: ce2257fa3a3dd898c87db315d272f82fd985f13d SHA-256: 5956a0a7da895b9207e8efc98d7d6cc54123b2a0d66e1f5c6b73e9dcb5755b94
342 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.001 PowerShell T1140 Deobfuscate/Decode Files or Information T1204.002 Malicious File

The sample contains a VBA project with a Document_Open macro, indicating an attempt to automatically execute malicious code upon opening. The VBA code utilizes obfuscation techniques, including reading reversed configuration from document properties and employing API calls like VirtualProtect, suggesting it's designed to load and execute a shellcode payload. ClamAV detection confirms its malicious nature as a downloader.

Heuristics 9

  • VBA property-stored shellcode loader critical OLE_VBA_PROPERTY_SHELLCODE_LOADER
    VBA auto-exec macro takes the address (VarPtr) of a byte buffer decoded from a document property, marks memory executable (VirtualProtect/VirtualAlloc), and transfers control through a callback API (e.g. SetTimer/EnumWindows). The payload is hidden in the document properties rather than the macro source — the SVCReady loader pattern, a native shellcode runner rather than a parser CVE.
  • ClamAV: Doc.Downloader.SVCReady-c5c43a913b3eccc9-9953477-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.SVCReady-c5c43a913b3eccc9-9953477-0
  • OOXML part with non-standard content type and high-entropy data high OOXML_BOGUS_CUSTOM_PART
    The package declares a part with an invented content type (not an OpenXML/Office/standard media type) holding large, high-entropy (likely encrypted/packed) data. Legitimate OOXML files do not carry opaque binary blobs under custom content types; this is the embedded next-stage payload pattern used by loaders such as SVCReady.
  • VBA project part renamed to evade filename detection high OOXML_VBA_PROJECT_RENAMED
    The VBA project is bound through the OOXML relationship/content type but its part is not named vbaProject.bin. Legitimate Office producers always emit vbaProject.bin; renaming it hides the macros from path-only scanners (observed in the SVCReady loader).
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • GetObject call high OLE_VBA_GETOBJ
    GetObject call
  • VBA reads reversed config from document properties high OLE_VBA_REVERSED_DOCPROP_CONFIG
    VBA applies StrReverse to values read from the document's custom/built-in properties. Storing reversed configuration (URLs, CLSIDs, env-var names, payload names) in document properties keeps indicators out of the macro source — an obfuscation technique used by the SVCReady loader.
  • VBA project inside OOXML medium OOXML_VBA
    Document contains a VBA project — VBA macros present (project part renamed away from vbaProject.bin: word/sZqaLWxDuf.bin)
  • 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://schemas.microsoft.com/office/word/2010/wordprocessingCanvas
    • http://schemas.microsoft.com/office/drawing/2014/chartex
    • http://schemas.microsoft.com/office/drawing/2015/9/8/chartex
    • http://schemas.microsoft.com/office/drawing/2015/10/21/chartex
    • http://schemas.microsoft.com/office/drawing/2016/5/9/chartex
    • http://schemas.microsoft.com/office/drawing/2016/5/10/chartex
    • http://schemas.microsoft.com/office/drawing/2016/5/11/chartex
    • http://schemas.microsoft.com/office/drawing/2016/5/12/chartex
    • http://schemas.microsoft.com/office/drawing/2016/5/13/chartex
    • http://schemas.microsoft.com/office/drawing/2016/5/14/chartex
    • http://schemas.openxmlformats.org/markup-compatibility/2006
    • http://schemas.microsoft.com/office/drawing/2016/ink
    • http://schemas.microsoft.com/office/drawing/2017/model3d
    • http://schemas.microsoft.com/office/2019/extlst
    • http://schemas.openxmlformats.org/officeDocument/2006/relationships
    • http://schemas.openxmlformats.org/officeDocument/2006/math
    • http://schemas.microsoft.com/office/word/2010/wordprocessingDrawing
    • http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawing
    • http://schemas.openxmlformats.org/wordprocessingml/2006/main
    • http://schemas.microsoft.com/office/word/2010/wordml
    • http://schemas.microsoft.com/office/word/2012/wordml
    • http://schemas.microsoft.com/office/word/2018/wordml/cex
    • http://schemas.microsoft.com/office/word/2016/wordml/cid
    • http://schemas.microsoft.com/office/word/2018/wordml
    • http://schemas.microsoft.com/office/word/2020/wordml/sdtdatahash
    • http://schemas.microsoft.com/office/word/2015/wordml/symex
    • http://schemas.microsoft.com/office/word/2010/wordprocessingGroup
    • http://schemas.microsoft.com/office/word/2010/wordprocessingInk
    • http://schemas.microsoft.com/office/word/2006/wordml
    • http://schemas.microsoft.com/office/word/2010/wordprocessingShape

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
b9231a52e916649a3ebf548a434d38b92ea56fde2dc42a1e363578042bd94ee6
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 6557 bytes
vbaProject_00.bin
50cadb16f808985e6b1d5ceede96668e3c4468314f0d236f891f95260d0f0792
vba-project OOXML VBA project: word/sZqaLWxDuf.bin 15360 bytes