Malicious RTF — malware analysis report

Static analysis result for SHA-256 556652db00857b5a…

MALICIOUS

RTF

5.6 KB First seen: 2021-02-23
MD5: 05a3e39e7d534b43f90b5737c800b8d2 SHA-1: b4caf64b954ef0162a658109e01d5a13c2c2540c SHA-256: 556652db00857b5af07d1af870cc9040deba73b3839e9a3bef08ce58fcdf5a97
282 Risk Score

Heuristics 7

  • SOAP Moniker — CVE-2017-8759 (SOAP WSDL RCE) critical CVE related CVE_2017_8759
    RTF \objdata decodes to OLE data containing the SOAP Moniker — CVE-2017-8759 (SOAP WSDL RCE) CLSID — the vulnerable control/moniker is embedded directly in the document's object stream, the delivery shape of this exploit. RTF objects auto-render when Word opens the file.
  • CVE-2017-0199 / CVE-2017-8759 (OLE2Link auto-activated remote loader) critical CVE related RTF_OLE2LINK_REMOTE_MONIKER_LOADER
    RTF embeds an OLE2Link object that is force-activated with \objupdate (no user interaction on open) and fetches a remote second stage — through an INCLUDETEXT/INCLUDEPICTURE field or the OLE object's own moniker. This is the OLE2Link auto-update attack path shared by CVE-2017-0199 (server returns an HTA/scriptlet) and CVE-2017-8759 (server returns a SOAP WSDL the .NET parser compiles). Office processes the fetched response through the same code path; the specific CVE depends on the now-unreachable server content type.
  • ClamAV: Rtf.Downloader.CVE_2017-6336326-3 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Downloader.CVE_2017-6336326-3
  • 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://schemas.microsoft.com/office/word/2003/wordml In RTF body

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000001a2.bin rtf-objdata-decoded RTF \objdata at offset 0x1A2 2600 bytes
SHA-256: d0a5b411256bce0706b8f956d0a538dcd36da857b13e1cd9e92d9f49369e6de8