Malicious RTF — malware analysis report

Static analysis result for SHA-256 ecf67ed4ba5f057a…

MALICIOUS

RTF

436.5 KB Created: 2020-03-22 17:37:00 First seen: 2020-05-14
MD5: b0d05dc918e285497474847e6734d6e0 SHA-1: fde8e906156b8a580c2d108ba5b47da27e18358d SHA-256: ecf67ed4ba5f057a0a140c45e605f90336bd16a03378694cdb6efdb1974d169e
182 Risk Score

Heuristics 6

  • Split hex Equation Editor ProgID + OLE object critical CVE likely RTF_EQUATION_EDITOR
    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.
  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    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.
  • \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 In RTF body

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00009ec3.bin rtf-objdata-decoded RTF \objdata at offset 0x9EC3 114294 bytes
SHA-256: 10b283a9ccd06dae1977d8e1e8bfa60227b3dc9875a0367a8b325e84599b320e