Malicious RTF — malware analysis report

Static analysis result for SHA-256 a33d2e4e73040b5d…

MALICIOUS

RTF

42.0 KB Created: 2018-06-03 16:28:00 First seen: 2018-09-04
MD5: dac9a8713de77c27fd68bc0ff12f2f84 SHA-1: e09a0a19b842dcc553d736ca7067fcda879b0b75 SHA-256: a33d2e4e73040b5dcd8bd7cdbb5f42ddbc445dcb87cc01a68def98414a4d9715
282 Risk Score

Malware Insights

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

The RTF file contains critical heuristics indicating exploitation of CVE-2017-0199 and CVE-2017-8759. It attempts to automatically link and update an OLE object, which is a common technique for exploiting these vulnerabilities. The embedded URL http://192.168.0.19/word.doc is likely used to download a secondary payload, such as a malicious document, to further compromise the system.

Heuristics 7

  • 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.
  • CVE-2017-0199 (OLE2Link / remote URL Moniker) critical CVE likely CVE_2017_0199
    RTF contains a URL Moniker OLE link whose decoded target is remote. Office can fetch and process the response through the CVE-2017-0199 OLE2Link attack path, but the server-side content type is not proven statically.
  • ClamAV: Rtf.Exploit.CVE_2017_0199-6335035-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2017_0199-6335035-0
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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 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://192.168.0.19/word.doc In RTF body
    • http://schemas.microsoft.com/office/word/2003/wordmlIn RTF body

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000291c.bin rtf-objdata-decoded RTF \objdata at offset 0x291C 2601 bytes
SHA-256: 016ee4493a8e27b81e8716c61ba075f91a198e54c11bf4fa617dca2803d02e7a