Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 91d735e10b2a11c6…

MALICIOUS

Office (OOXML)

80.8 KB Created: 2013-10-31 15:25:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2021-09-29
MD5: a9ffe337d6a48d5c1a0b22fb2d33ee6b SHA-1: bf4dda844df5f462a9c257910776426f44e820a1 SHA-256: 91d735e10b2a11c659a30d8924d44d0efa28a963a38b0d3d15a3b8b5154d2ccf
142 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The sample is identified as malicious due to critical heuristic firings indicating exploitation of CVE-2021-40444 via an external OLEObject gadget. This vulnerability is commonly leveraged to download and execute arbitrary code from a remote source. The embedded URL http://192.168.146.128/test.txt is highly suspicious and likely serves as the initial stage for a payload delivery.

Heuristics 4

  • External OLEObject gadget — CVE-2021-40444 critical CVE exact CVE_2021_40444
    External relationship to MHTML:http://192.168.146.128/test.txt!http://192.168.146.128/test.txt — exploitable external OLEObject gadget pattern for CVE-2021-40444
  • ClamAV: Doc.Exploit.CVE-2021-40444-9891698-2 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Exploit.CVE-2021-40444-9891698-2
  • External relationship medium OOXML_EXTERNAL_REL
    External target in word/_rels/document.xml.rels: MHTML:http://192.168.146.128/test.txt!http://192.168.146.128/test.txt
  • 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://192.168.146.128/test.txt!http://192.168.146.128/test.txt OOXML external relationship
    • http://schemas.microsoft.com/office/word/2010/wordprocessingCanvasIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2014/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2015/9/8/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2015/10/21/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/9/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/10/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/11/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/12/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/13/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/14/chartexIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/markup-compatibility/2006In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/inkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2017/model3dIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/relationshipsIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/mathIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingDrawingIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawingIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/wordprocessingml/2006/mainIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2012/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2016/wordml/cidIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2015/wordml/symexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingGroupIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingInkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2006/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingShapeIn document text (OOXML body / shared strings)