Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 9582f0ffe1b9e4f3…

MALICIOUS

RTF / .DOC

844.9 KB Created: 2019-09-17 13:59:00
MD5: 3ba2b21d313b2be4dadd5137562511a5 SHA-1: a339660eb6f14b3b66014fe599b98bb16aa0a760 SHA-256: 9582f0ffe1b9e4f3a3f87b20590c99adda4fc948f5e2108fe1a218ad2b92ac04
200 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The file is an RTF document containing an embedded OLE object, specifically triggering the Equation Editor. Critical heuristics indicate exploitation of CVE-2017-8759, a known vulnerability allowing for arbitrary code execution. The embedded object data is likely a payload designed to be activated via ".objupdate".

Heuristics 6

  • CVE-2017-8759 — MSXML SAX OLE activation critical CVE likely CVE_2017_8759
    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 CLSID critical RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • \objupdate forces OLE activation high RTF_OBJUPDATE
    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
    RTF contains 1 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    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 http://schemas.microsoft.com/office/word/2003/wordml

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000ca19c.bin
9bf1c77079d83d262a796e6038fbc783cc004f185e6d784c1dc7c1653d9dcc6a
rtf-objdata-decoded RTF \objdata at offset 0xCA19C 3739 bytes