Emotet — Office (OOXML) / .DOC malware analysis

Static analysis result for SHA-256 4aec6177778f357b…

MALICIOUS

Office (OOXML) / .DOC

88.0 KB Created: 2021-12-08 18:15:00 UTC Authoring application: Microsoft Office Word 16.0000
MD5: 623024838e3aec178ffb8b50a3321fae SHA-1: c19f49d67f8c780cc348a6246043c9f365919aef SHA-256: 4aec6177778f357b4014f543abadd7fec5b5ac8df13e8a4c7c9dcfe1f4458aa1
202 Risk Score

Malware Insights

Emotet · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1059.003 Windows Command Shell

The sample is identified as malicious by ClamAV with the signature 'Doc.Downloader.EmotetUpdate122100-9914334-1'. The embedded VBA macro contains an AutoOpen function which is triggered upon opening the document. This macro reconstructs a string from the document's keywords, saves the document with that name, and then executes the saved file using 'c:\windows\explorer.exe'. This behavior is characteristic of Emotet's downloader functionality, which typically executes a second-stage payload.

Heuristics 6

  • ClamAV: Doc.Downloader.EmotetUpdate122100-9914334-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetUpdate122100-9914334-1
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • Suspicious extracted artifact high 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.
  • VBA project inside OOXML medium OOXML_VBA
    Document contains vbaProject.bin — 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.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/2012/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
446de911192ce6c25ce4bd5ae51b56b73f1b91e83cb9f41cc004c7c587af3a58
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 978 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.
vbaProject_00.bin
7fcf6042099974efcce9ccb0c30bb4b0315a9924479bd7c4cb571ba39cc68e04
vba-project OOXML VBA project: word/vbaProject.bin 14336 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.