Malicious RTF — malware analysis report

Static analysis result for SHA-256 b2ff4d752d7d6a52…

MALICIOUS

RTF

310.7 KB
MD5: 1deeb6163376b1e755084f5e04e8d8af SHA-1: 5cc1ac8b03aee1bcd4c82f071e5181f1e992502b SHA-256: b2ff4d752d7d6a52cde5f6f57889c454dd8a856c511368d1839ad898241ecb4d
122 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object that is activated via \objupdate, triggering the Equation Editor. Analysis of the decoded Equation Editor payload reveals it is a PE file, indicating a likely exploit. This pattern is commonly used to download and execute a second-stage payload, leading to a high confidence assessment of this attack vector.

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_off000010a5.bin
3c2d885891b0ca8c5c22619e5da87af0a23842688ba980df62ef3dd7bd4e340d
rtf-objdata-decoded RTF \objdata at offset 0x10A5 156698 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.