Malicious RTF — malware analysis report

Static analysis result for SHA-256 bfaa8d24fea8f904…

MALICIOUS

RTF

68.8 KB Created: 2020-12-20 07:12:00 First seen: 2021-01-15
MD5: c92901f2ef13374f4afd950d840e02c1 SHA-1: 69a8ec206dc0a80bb675277273bb806330d92805 SHA-256: bfaa8d24fea8f904b33da90bc2836785c390c3adaec01ac8082c953dd7b787ed
242 Risk Score

Heuristics 6

  • Equation Editor CLSID critical CVE likely RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • CVE-2018-0798 — Equation Editor Matrix record overflow critical CVE exact CVE_2018_0798
    RTF contains hex-encoded MTEF Matrix record exploit signature (NOP-sled 0x60 + padding 0x61 + return address 0x0BFB). CVE-2018-0798 exploits a stack buffer overflow in EQNEDT32.EXE's Matrix record parser and affected Equation Editor broadly, including builds patched for CVE-2017-11882. Widely used by APT groups (Conimes, KeyBoy, Emissary Panda, Rancor).
  • ClamAV: Rtf.Exploit.CVE_2018_0802-6825822-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2018_0802-6825822-0
  • \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 2 \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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000abe2.bin rtf-objdata-decoded RTF \objdata at offset 0xABE2 13198 bytes
SHA-256: 9a1726d0e05c5c44db90744f19a2888c23b65ed02b6fffc71153434861cb320c
objdata_01_off0000b6b2.bin rtf-objdata-decoded RTF \objdata at offset 0xB6B2 11820 bytes
SHA-256: b4b0cdd1bfe8a8248066883c52ca5367416cd8887737f64f4884cb0fa5bb661f