Malicious Office (OLE) / .DOCX — malware analysis report

Static analysis result for SHA-256 134eb9d7a15d7538…

MALICIOUS

Office (OLE) / .DOCX

161.9 KB Created: 2021-01-04 16:15:00 Authoring application: Microsoft Office Word
MD5: 4365f218bfd1df947bb0ef6f97486405 SHA-1: 464b66ea65d411d4e8c69122bc3ef2f344b8ab3b SHA-256: 134eb9d7a15d7538aa3864363721e2a1e4d897a99d5dbb1cade99d4c45e42180
262 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1105 Ingress Tool Transfer T1036 Masquerading

The sample contains a VBA macro that is triggered by the Document_Open event. This macro utilizes CreateObject to instantiate a Scripting.FileSystemObject, which is then used to create and write to files on the filesystem. The obfuscation of 'Scripting.FileSystemObject' from split string literals indicates malicious intent. The ClamAV detection as 'Doc.Downloader.EmotetRed02224-9938637-0' further supports its classification as a downloader.

Heuristics 7

  • Dangerous API name reassembled from split string literals critical OLE_VBA_SPLIT_KEYWORD_OBFUSCATION
    VBA concatenates short string literals that reassemble a dangerous API/ProgID/LOLBin name (e.g. Scripting.FileSystemObject, WScript.Shell, powershell, URLDownloadToFile) which appears in no single literal. Splitting an API name across string concatenation is done only to evade keyword scanning.
  • ClamAV: Doc.Downloader.EmotetRed02224-9938637-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetRed02224-9938637-0
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open 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 macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code
  • 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.openxmlformats.org/drawingml/2006/main

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
b7c08445609ad3b9c2a0766b1423df26453c524cbf6c8eca0da53a1732c00612
vba-macro oletools.olevba.extract_macros (decoded VBA source) 7252 bytes