Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 ac71378fa1338243…

MALICIOUS

Office (OOXML)

20.8 KB Created: 2021-07-11 09:14:00 UTC Authoring application: Microsoft Office Word 16.0000
MD5: d14f51ab73f5df9cbad0592d59765981 SHA-1: c9a8da39caf830741594f8056c6b95f7230d366c SHA-256: ac71378fa1338243c2a957d9b89d4e2e64b0a91a02affce1a505e6fd2b671efb
182 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The file is an OOXML document containing VBA macros, specifically an AutoOpen macro, which is a common technique for executing malicious code upon opening. ClamAV signatures also confirm its malicious nature. The VBA code includes API calls for process creation and manipulation, indicating an intent to download and execute a secondary payload. The presence of the AutoOpen macro strongly suggests this document was intended to be delivered as a spearphishing attachment.

Heuristics 5

  • ClamAV: Doc.Malware.Valyria-10015188-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Malware.Valyria-10015188-0
  • 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 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
6d65acb85bf065879ac482566e398503a671a4c825b2ca12aa86e6b4b03b0b64
vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 4416 bytes
vbaProject_00.bin
a1c0cbe82b9061aa841363de0ef08e3d2e035d073fe5418be116dcedafc5fdae
vba-project OOXML VBA project: word/vbaProject.bin 22016 bytes
Detection
ClamAV: Doc.Malware.Valyria-10015188-0
Obfuscation or payload: unlikely