Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 40d43e4cdc591e96…

MALICIOUS

RTF / .DOC

422.2 KB
MD5: f5d04bebad73b07396f217e4f8b37b5d SHA-1: 5574a572436c645657395347fd318924322b9a25 SHA-256: 40d43e4cdc591e96bb83c34032a4b8272ea218ea4a18685e46a8d1774f785ecf
122 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The RTF file contains an embedded OLE object that leverages the Equation Editor vulnerability. This technique is commonly used to deliver a second-stage payload. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` heuristics strongly indicates an exploit targeting this component, likely leading to arbitrary code execution.

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_off00000065.bin
b80b0b02024e5bb780bfecc03888b530542779928b6b1c1178aa280f31d4d7ce
rtf-objdata-decoded RTF \objdata at offset 0x65 216041 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.