Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 ed1b91674289984e…

MALICIOUS

RTF / .DOC

43.1 KB
MD5: 73215bf89a2f970684183f8f609e9d37 SHA-1: bf1fc69c0ea37cf628f46a4828d4a452169f5c2e SHA-256: ed1b91674289984e6ee4c7afa8e0bb18565d52c15bd4999e3944a06fd7ca6569
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains embedded OLE objects, specifically triggering critical heuristics related to Equation Editor vulnerabilities. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` strongly indicates an attempt to exploit a known vulnerability in the Equation Editor component to achieve arbitrary code execution upon opening the document. This is a common delivery mechanism for initial access.

Heuristics 4

  • Split hex Equation Editor ProgID + OLE object critical 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.
  • 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_off0000188a.bin
e3ca795e5035b3e87c3ba07d6f3832da28e47dd1a9b3114fe0fa78073bdd4252
rtf-objdata-decoded RTF \objdata at offset 0x188A 2044 bytes