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

Static analysis result for SHA-256 0f188a5741c7753b…

MALICIOUS

Office (OOXML) / .DOC

33.9 KB Created: 2017-05-25 19:12:00 UTC Authoring application: Microsoft Macintosh Word 14.0000
MD5: 6a5c5c5325024b73fb6189ac0fd668d9 SHA-1: 0222c54bdf99491e82451c6d48bb5bb5233c9888 SHA-256: 0f188a5741c7753b90d4e51b6096541e018abfb3db33d502d718ccc29f89e98b
442 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059 Command and Scripting Interpreter T1204.002 Malicious File T1566.001 Spearphishing Attachment

The sample contains VBA macros that execute automatically upon opening, leveraging WScript.Shell and CreateObject to write and execute a decoded payload. The AutoOpen macro attempts to decode a Base64 string from the document's 'Comments' property and then executes it, either as a Windows executable or via Python on macOS. This indicates a downloader or dropper functionality.

Heuristics 10

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • WScript.Shell usage critical OLE_VBA_WSCRIPT
    WScript.Shell usage
  • Obfuscated VBA Shell command with URL critical OLE_VBA_OBFUSCATED_SHELL_URL
    VBA macro invokes Shell with command text assembled through decoder or string-manipulation functions and includes a URL. This is a high-confidence downloader/dropper pattern, stronger than Shell or URL evidence on their own.
  • ClamAV: Doc.Malware.Valyria-6728957-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Malware.Valyria-6728957-0
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
  • VBA project inside OOXML medium OOXML_VBA
    Document contains a VBA project — VBA macros present
  • 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://www.motobit.com
    • http://Motobit.cz
    • http://schemas.microsoft.com/office/word/2010/wordprocessingCanvas
    • http://schemas.microsoft.com/office/mac/office/2008/main
    • http://schemas.openxmlformats.org/markup-compatibility/2006
    • 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/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
3fbc2ef94a618e17d5a6ba5af930717982f8239ff4eded5753681755be17f4ca
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 2931 bytes
vbaProject_00.bin
635a875e3ae07b99a521c0222d87b4cab342ce6b00fdce8cbae6e5f81dd4492f
vba-project OOXML VBA project: word/vbaProject.bin 15872 bytes
Detection
ClamAV: Doc.Malware.Valyria-6728957-0
Obfuscation or payload: unlikely