Malicious RTF — malware analysis report

Static analysis result for SHA-256 cea76cc53fbe6b76…

MALICIOUS

RTF

273.3 KB Created: 2019-08-29 07:24:00 First seen: 2020-05-14
MD5: 9c5e06fc545f055b998ff91afd37f49e SHA-1: ca2e0b30cc4be662bcb3baf40a71b40097520979 SHA-256: cea76cc53fbe6b765e149e03b3f33bd83a1bdef3e5f986cb2e69a0dc680d8c19
142 Risk Score

Heuristics 4

  • CVE-2017-11882 — Equation Editor FONT record overflow critical CVE likely CVE_2017_11882
    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.
  • Equation Editor shellcode downloads a second-stage payload critical OLE_MTEF_SHELLCODE_DOWNLOAD_URL
    The shellcode reached by the Equation Editor overflow resolves download/exec APIs (URLDownloadToFile / ShellExecute / WinExec) and fetches a second-stage payload. The download URL was recovered from the Equation Native stream — directly when the shellcode is plaintext, or by emulating its self-decoding stub. An integer-encoded host (e.g. http://000030000706151) is normalised to its dotted-quad form and both spellings are surfaced as IOCs.
  • 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://mafud.company/ew.msi In RTF body
    • http://000030000706151In RTF body
    • http://192.3.140.105Decoded from obfuscated IP host (000030000706151)
    • http://schemas.microsoft.com/office/word/2003/wordmlIn RTF body

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000a7f3.bin rtf-objdata-decoded RTF \objdata at offset 0xA7F3 15672 bytes
SHA-256: fac53731d6e376c9ef183c38658695b6140d8066a677f091d32a8b7c11bed47a