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

Static analysis result for SHA-256 098b49c651033ea4…

MALICIOUS

Office (OOXML) / .DOC

127.5 KB Created: 2020-09-23 10:05:00 UTC Authoring application: Microsoft Office Word 16.0000
MD5: 25a2a9a49731214dd80edd89c1fdb915 SHA-1: 5ff81459c157ceff1890aa3241a85d92ae8babd4 SHA-256: 098b49c651033ea4248aa17ee3329b9f4acbbba65bcfc0fcdb73c1a26a3da48c
322 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059 Command and Scripting Interpreter T1204.002 Malicious File T1105 Ingress Tool Transfer

This OOXML document contains VBA macros, including an AutoOpen macro, which is a common technique for malicious documents. The script uses the Shell() function and CreateObject to download and save a file as 'c:\programdata\d9cc4.pdf', likely a second-stage payload. The presence of VBA macros and the use of Shell() and CreateObject strongly indicate a malicious dropper.

Heuristics 8

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • ClamAV: Doc.Dropper.Mrdy-9765642-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Mrdy-9765642-0
  • 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://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.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/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
2cf65be882ff35822d4ba2738305aefa6cd1eac06042076fedc336e9cdf8fba7
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 12869 bytes
vbaProject_00.bin
76bd0592d98a1827564c85936f0522329412c22ecb6bbe6df402e9e2269335d1
vba-project OOXML VBA project: word/vbaProject.bin 45568 bytes
Detection
ClamAV: Doc.Dropper.Mrdy-9765642-0
Obfuscation or payload: unlikely