Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 462612f8beb46fdd…

MALICIOUS

RTF / .DOC

379.5 KB
MD5: 5d96452c3067bb9896f88c52bb6b6ed1 SHA-1: 38ee4d2fa51142c1055f0870705bd99c1cec45b1 SHA-256: 462612f8beb46fdd79ebe45b7fd528f07a800aa62c19749a73075dfa334d8090
222 Risk Score

Malware Insights

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

The RTF document contains an OLE object that leverages the Equation Editor vulnerability (CVE-2017-11882). This vulnerability is known to be used for dropping and executing arbitrary code. The decoded object is a PE file, indicating it's the payload. No further details on the payload's behavior are available from static analysis.

Heuristics 6

  • Equation Editor OLE1 native payload — CVE-2017-11882 related critical CVE related CVE_2017_11882_RELATED
    RTF decodes to an OLE1 Equation.3 embedded object whose native data is large and payload-like, and \objupdate requests automatic activation. This is the delivery shape used by Equation Editor RCE documents such as CVE-2017-11882/CVE-2018-0802, but the malformed MTEF record needed for exact attribution was not recovered.
  • 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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off00000055.bin
55e198b3d8923cb33fe82697cd5d040eed6c1a4d0ef3cd11057a5fc541725d7a
rtf-objdata-decoded RTF \objdata at offset 0x55 193995 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.