Ursnif — Office (OOXML) / .DOCX malware analysis

Static analysis result for SHA-256 5fc145ebae076978…

MALICIOUS

Office (OOXML) / .DOCX

124.4 KB Created: 2020-03-26 01:35:00 UTC Authoring application: Microsoft Office Word 16.0000
MD5: 4985580c47c3240b969dfe11f4f4b3a2 SHA-1: f12ace46508771a4fbbffef3a87b8397b6eda39b SHA-256: 5fc145ebae076978b7afd5bdada2e98e33d8848d876955b16c10622c0251d5b0
262 Risk Score

Malware Insights

Ursnif · confidence 95%

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

The sample contains a VBA macro with an AutoOpen subroutine that executes a main function. This function reconstructs and copies cmd.exe to C:\Users\Public\data\orgmardam\mtl.exe, and then executes it. This behavior is indicative of a downloader, consistent with the Ursnif family, and is flagged by multiple critical heuristics.

Heuristics 7

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • ClamAV: Doc.Downloader.UrsnifDE0-7640644-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.UrsnifDE0-7640644-0
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • 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.
  • 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 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/2016/wordml/cid
    • 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
    • http://ns.adobe.com/xap/1.0/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/sType/ResourceEvent#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/photoshop/1.0/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
1fe4ba30def3733aebef2afc63278c49bcb27acd0ed333adeae4bb2557d5f701
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 2293 bytes
vbaProject_00.bin
d09327f87ba02e75aa79f7ad6cfd7904542af7ee578fe5786e2b068a4b03ce2b
vba-project OOXML VBA project: word/vbaProject.bin 62976 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).