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

Static analysis result for SHA-256 629ce9a17b978471…

MALICIOUS

Office (OOXML) / .DOC

117.2 KB Created: 2020-06-24 09:06:00 UTC Authoring application: Microsoft Office Word 16.0000
MD5: f12750a0f1646c1935ca5ec0467eda19 SHA-1: 28a29ee3ea3e12a61864ffd115ba0f021287cfe0 SHA-256: 629ce9a17b978471c1740d0a2931f5043c3e51f52ec5dc351019255f4161d266
342 Risk Score

Malware Insights

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

The sample is a malicious OOXML document containing a VBA macro that automatically executes upon opening. The macro utilizes URLDownloadToFile to download a payload from a remote source and WScript.Shell.Exec to execute it. This indicates a downloader functionality designed to fetch and run a second-stage malicious artifact.

Heuristics 8

  • URLDownloadToFile in VBA critical OLE_VBA_DOWNLOAD
    URLDownloadToFile in VBA
  • VBA URLDownloadToFile reversed-LOLBin launcher critical OLE_VBA_URLDOWNLOAD_REVERSED_LOLBIN
    VBA auto-exec macro downloads a payload with URLDownloadToFile and launches it through WScript.Shell.Exec using a reversed command string. This is a high-confidence downloader/launcher pattern, not an Office parser CVE.
  • ClamAV: Doc.Downloader.Mrkb-8213933-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Mrkb-8213933-0
  • 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
  • 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
59a02ebfa8711c9c3b1d6f8cec18d9280f490c43a56542aadb150eed020d7c54
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 4663 bytes
vbaProject_00.bin
c1f9819c9155f8e36b662be69b7576c86eba015862cf15b6d5a23a82c5c28207
vba-project OOXML VBA project: word/vbaProject.bin 28672 bytes
Detection
ClamAV: Doc.Downloader.Mrkb-8213933-0
Obfuscation or payload: unlikely