MALICIOUS
522
Risk Score
Malware Insights
MITRE ATT&CK
T1566.001 Spearphishing Attachment
T1203 Exploitation for Client Execution
The sample is a malicious OOXML document that leverages an embedded RTF object to exploit CVE-2017-11882 and CVE-2017-8759. The RTF object contains a PE header, indicating it is designed to execute a payload. The altChunk mechanism is used to import this RTF content, and auto-update features are configured to trigger the execution of the embedded executable. No specific malware family could be identified, but the exploitation technique is clear.
Heuristics 12
-
CVE-2017-11882 — Equation Editor FONT record overflow critical CVE likely CVE_2017_11882(in altChunk RTF word/Acronym.rtf) Equation Editor MTEF contains an overlong FONT typeface field, the vulnerable copy primitive for CVE-2017-11882. This is stronger evidence than the Equation Editor CLSID alone because it identifies the malformed record that drives code execution in EQNEDT32.EXE.
-
CVE-2017-8759 — MSXML SAX OLE activation critical CVE likely CVE_2017_8759(in altChunk RTF word/Acronym.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.
-
Composite Moniker in RTF OLE object high RTF_COMPOSITE_MONIKER_RELATED(in altChunk RTF word/Acronym.rtf) RTF contains Composite Moniker CLSID in OLE object context, but no nearby scriptlet/SCT payload was confirmed. Treat as related moniker attack-surface evidence rather than proof of CVE-2017-8570 exploitation.
-
altChunk imports embedded RTF (RTF injection) critical OOXML_ALTCHUNK_RTFDocument 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/Acronym.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.
-
PE header (with DOS stub) in hex data critical RTF_MZ_HEX(in altChunk RTF word/Acronym.rtf) Hex-encoded PE (MZ + DOS stub) found inside RTF — likely an embedded executable payload
-
altChunk RTF auto-updates embedded executable object critical OOXML_ALTCHUNK_RTF_AUTOUPDATE_PEOOXML document imports an embedded RTF through altChunk; the RTF contains OLE object data, forces object update, and carries a hex-encoded PE payload. This is a stronger compound exploit-loader shape than a generic altChunk RTF wrapper, but it is not tied to a single CVE unless the nested RTF object primitive also matches one.
-
\objupdate forces OLE activation high RTF_OBJUPDATE(in altChunk RTF word/Acronym.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.
-
Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX(in altChunk RTF word/Acronym.rtf) RTF contains ~1431KB of hex-encoded data inside \objdata sections — may hide a payload
-
OLE object data medium RTF_OBJDATA(in altChunk RTF word/Acronym.rtf) RTF contains 2 \objdata section(s) — embedded OLE objects
-
Embedded OLE object medium RTF_OBJEMB(in altChunk RTF word/Acronym.rtf) RTF contains \objemb — embedded OLE object
-
Embedded URL info EMBEDDED_URLOne 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://opendope.org/xpaths
- http://opendope.org/conditions
- http://opendope.org/questions
- http://opendope.org/components
- http://opendope.org/SmartArt/DataHierarchy
- http://www.pdf-tools.com\
- http://ocsp.entrust.net00
- http://ocsp.entrust.net05
- http://schemas.openxmlformats.org/wordprocessingml/2006/main
- http://schemas.openxmlformats.org/officeDocument/2006/math
- http://schemas.openxmlformats.org/officeDocument/2006/relationships
- http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawing
- http://schemas.openxmlformats.org/drawingml/2006/main
- http://schemas.openxmlformats.org/schemaLibrary/2006/main
- http://schemas.openxmlformats.org/drawingml/2006/chart
- http://schemas.openxmlformats.org/drawingml/2006/chartDrawing
- http://schemas.openxmlformats.org/drawingml/2006/diagram
- http://schemas.openxmlformats.org/drawingml/2006/picture
- http://schemas.openxmlformats.org/drawingml/2006/spreadsheetDrawing
- http://schemas.microsoft.com/office/drawing/2008/diagram
- http://schemas.openxmlformats.org/officeDocument/2006/bibliography
- http://schemas.openxmlformats.org/drawingml/2006/compatibility
- http://schemas.openxmlformats.org/drawingml/2006/lockedCanvas
- http://www.adobe.com/go/security-and-compliance
- https://acrobat.adobe.com/us/en/
- http://www.pdf-tools.com
- http://www.w3.org/1999/02/22-rdf-syntax-ns#
- http://purl.org/dc/elements/1.1/
- http://ns.adobe.com/xap/1.0/
- http://ns.adobe.com/xap/1.0/mm/
- http://ns.adobe.com/xap/1.0/sType/ResourceRef#
- http://ns.adobe.com/xap/1.0/sType/ResourceEvent#
- http://ns.adobe.com/pdf/1.3/
- http://crl.entrust.net/g2ca.crl0
- http://www.entrust.net/rpa0
- http://aia.entrust.net/ovcs1-chain256.cer01
- http://crl.entrust.net/ovcs1.crl0J
- https://www.globalsign.com/repository/0
- http://ocsp.globalsign.com/ca/gstsacasha384g40C
- http://secure.globalsign.com/cacert/gstsacasha384g4.crt0
- http://crl.globalsign.com/ca/gstsacasha384g4.crl0
- http://ocsp2.globalsign.com/rootr606
- http://crl.globalsign.com/root-r6.crl0G
Extracted artifacts 2
Files carved from inside the sample during analysis.
| Filename | Kind | Source | Size |
|---|---|---|---|
objdata_00_off00003a12.bin35276d71d9997b6bd1057e45dc2e11de6d507ce96a3c692af2c3b5eaacc872ab |
rtf-objdata-decoded | RTF \objdata at offset 0x3A12 | 728714 bytes |
objdata_01_off00172f58.bine1f3559241a80335443d4d0c1964ccd8e69099cdcc0985e3ea0b86b89e746883 |
rtf-objdata-decoded | RTF \objdata at offset 0x172F58 | 584546 bytes |
Open this report in the interactive analyzer, or submit your own file for analysis.