Malicious RTF — malware analysis report

Static analysis result for SHA-256 ec02e391d1868f60…

MALICIOUS

RTF

8.2 KB First seen: 2019-01-12
MD5: 47b9571092572edcefd6bd9800928bce SHA-1: eb6ae5698e0b44f230f939a264aab19eda2a43bf SHA-256: ec02e391d1868f603961ddc5d2ecdf69c5ace3e9d037dba2de1b2698341e0c82
240 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The RTF file contains an embedded OLE object that triggers CVE-2017-11882, a critical vulnerability in Microsoft Equation Editor. This exploit allows for arbitrary code execution upon opening the document. No document body text or scripts were extracted, but the presence of the Equation Editor exploit is a strong indicator of malicious intent.

Heuristics 5

  • 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-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.
  • ClamAV: Doc.Exploit.CVE_2017_11882-6934206-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Exploit.CVE_2017_11882-6934206-0
  • \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 1 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000003b.bin rtf-objdata-decoded RTF \objdata at offset 0x3B 4142 bytes
SHA-256: 8dfac48d7301c06c79b4ab438adb188d143a0e325dec9cece2c36f3ed4ebeaa9