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

Static analysis result for SHA-256 dcd24c86c61fa88d…

MALICIOUS

Office (OOXML) / .DOCX

298.6 KB Created: 2026-01-10 16:34:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2026-03-03
MD5: 7ae255a40b4d91d1fc9d4dee57a89be1 SHA-1: 0b3f4942dc4391a4b12dc2d3bce69b859677e8f5 SHA-256: dcd24c86c61fa88d37f17be33b8a047e565599885d467db29c571a6279ff4ad0
342 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1204.002 Malicious File

The sample leverages multiple critical vulnerabilities including CVE-2017-11882 (Equation Editor) and CVE-2017-8759 (MSXML SAX OLE activation) via an embedded RTF object. The presence of RTF injection and OLE object data strongly indicates an exploit attempt. The CVE-2026-21514 finding further supports the exploitation of Word/OLE security bypasses. The primary attack vector is the exploitation of these known vulnerabilities to achieve arbitrary code execution.

Heuristics 9

  • CVE-2017-8759 — MSXML SAX OLE activation critical CVE likely CVE_2017_8759
    (in altChunk RTF word/paral.rtf) RTF contains a hex-encoded OLE1 object for Msxml2.SAXXMLReader.6.0 followed by an embedded OLE compound document, and the document requests OLE activation. This matches the RTF staging shape used for CVE-2017-8759 SOAP/WSDL parser code injection.
  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    (in altChunk RTF word/paral.rtf) RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • CVE-2026-21514 — Word/OLE security bypass in RTF high CVE likely CVE_2026_21514
    (in altChunk RTF word/paral.rtf) RTF contains a hidden \svb hex package with DrsE2oDoc and downRevStg drawing compatibility parts. This matches an observed CVE-2026-21514 exploitation shape that manipulates Word's internal document structure and trust decisions.
  • altChunk imports embedded RTF (RTF injection) critical OOXML_ALTCHUNK_RTF
    Document inlines an embedded RTF via an aFChunk relationship and a <w:altChunk> body element. This is the canonical RTF-injection wrapper used to smuggle RTF exploits (Equation Editor / URL Moniker / objdata) past DOCX-only scanners. Word opens the wrapper and executes the RTF inline. Recursing into the RTF for the exact exploit primitive.
  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    (in altChunk RTF word/paral.rtf) RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • \objupdate forces OLE activation high RTF_OBJUPDATE
    (in altChunk RTF word/paral.rtf) RTF contains \objupdate — forces automatic OLE object instantiation when the document is opened, bypassing user interaction. Almost exclusively seen in Equation Editor exploit documents.
  • OLE object data medium RTF_OBJDATA
    (in altChunk RTF word/paral.rtf) RTF contains 2 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    (in altChunk RTF word/paral.rtf) RTF contains \objemb — embedded OLE object
  • 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 https://asakura.in/upload/upl/BlAyiEmDNBOtrlFW_W9T.docx
    • 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
    • http://schemas.microsoft.com/office/2006/metadata/properties
    • http://www.w3.org/2001/XMLSchema-instance
    • http://schemas.microsoft.com/office/infopath/2007/PartnerControls
    • http://schemas.openxmlformats.org/officeDocument/2006/customXml
    • http://schemas.microsoft.com/office/2006/metadata/contentType
    • http://schemas.microsoft.com/office/2006/metadata/properties/metaAttributes
    • http://www.w3.org/2001/XMLSchema
    • http://schemas.microsoft.com/office/2006/documentManagement/types
    • http://schemas.openxmlformats.org/package/2006/metadata/core-properties
    • http://purl.org/dc/elements/1.1/
    • http://purl.org/dc/terms/
    • http://schemas.microsoft.com/internal/obd
    • http://dublincore.org/schemas/xmls/qdc/2003/04/02/dc.xsd
    • http://dublincore.org/schemas/xmls/qdc/2003/04/02/dcterms.xsd
    • http://schemas.microsoft.com/sharepoint/v3/contenttype/forms
    • http://schemas.openxmlformats.org/officeDocument/2006/cus�

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000af79f.bin
5f19d2d5940ae369890891cf8bf019fe552fa3c57f079278483285f569a01481
rtf-objdata-decoded RTF \objdata at offset 0xAF79F 13902 bytes
objdata_01_off000c1b97.bin
84d47208057ac323bbd82f9bcfcc19d412ab8201f50ce8c41bf02dc7e9f53faa
rtf-objdata-decoded RTF \objdata at offset 0xC1B97 584826 bytes
rtf_svb_00000009.zip
28fc295dafc0bcccd998d6dc34a4e9ae47eb34cb74cb4b892eb6454833467799
rtf-svb-package RTF \svb hex-decoded ZIP at offset 0x9 116932 bytes