Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d2b43b33e6f83539…

MALICIOUS

RTF / .DOC

367.2 KB
MD5: e1677bff46511aa462e5bd9754816e6a SHA-1: d24518704071495fe7b3bb86ea1fe72ac01191e4 SHA-256: d2b43b33e6f835390fe3102d83049cce1f8c7bb33f6613283391140b857c0d05
122 Risk Score

Malware Insights

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

The sample is an RTF document containing an OLE object that exploits the Equation Editor vulnerability. The ".objupdate" directive forces OLE activation, indicating an attempt to execute embedded code. The extracted "objdata" artifact suggests the presence of a secondary payload. While no specific family is identified, the attack pattern is consistent with exploit delivery via a weaponized document.

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.
  • \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
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001135.bin
438859b383a9f152e97cd1c6086a05e6dd417eabc594d159059001b52ae82a72
rtf-objdata-decoded RTF \objdata at offset 0x1135 185732 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.