Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 8efa32dfacb19871…

MALICIOUS

RTF / .DOC

8.8 KB
MD5: 73d6f3936c099345af82c67abef91578 SHA-1: d23184c2ed86950207162b748c220bcb2bdf2827 SHA-256: 8efa32dfacb19871cdd5d7c726ca32cb29ef4a7a1ed707dbd90e33d116172e83
280 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1559.002 Component Object Model and Distributed Component Object Model

The sample is an RTF document containing embedded OLE objects, specifically triggering critical heuristics for Equation Editor vulnerabilities. The presence of RTF_EQUATION_EDITOR and CVE_2017_11882 firings strongly indicates exploitation of the Equation Editor vulnerability. This technique is commonly used to achieve arbitrary code execution on the victim's machine.

Heuristics 6

  • 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 CLSID critical RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • ClamAV: Rtf.Exploit.CVE_2018_0802-6825822-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2018_0802-6825822-0
  • 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 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000000be.bin
67f297bb7a5ffd50e2e3d6c3ddbc6afe4f20370625d348e3d132d74cd3ed3db4
rtf-objdata-decoded RTF \objdata at offset 0xBE 4165 bytes