Malicious RTF — malware analysis report

Static analysis result for SHA-256 3c8204c297ec7d8d…

MALICIOUS

RTF

688.7 KB
MD5: 8c3bd74f070472712c19313afc20ea37 SHA-1: d1e0a8e6b0fb64a6de19ac2bb11c924ecc7cfe68 SHA-256: 3c8204c297ec7d8ddcb7ebcc16c3e3cf4fdee5abb1cb132bee6ba72c137ce47c
122 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object that decodes to a PE file, indicative of an Equation Editor exploit. The ".objupdate" directive suggests that the OLE object is automatically activated upon opening the document. The extracted artifact 'objdata_00_off00000043.bin' is the decoded payload, likely a secondary stage downloader or dropper.

Heuristics 4

  • Decoded Equation Editor payload + PE critical RTF_EQUATION_EDITOR
    RTF decodes to an Equation Editor ProgID adjacent to OLE activation and the same decoded object stream contains embedded PE bytes. This matches the Equation Editor exploit surface used by CVE-2017-11882 / CVE-2018-0802 documents, while requiring payload evidence to avoid flagging benign Equation references.
  • \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_off00000043.bin
0d31770d9077c263ade42e09c1660b4ec8605affeff747c011148184e8be6feb
rtf-objdata-decoded RTF \objdata at offset 0x43 352460 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.