Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 320592aa53514c7f…

MALICIOUS

RTF / .DOC

526.6 KB
MD5: ed75e6e71d66d381295826453ae631e0 SHA-1: b7c29ebe55ac21e5893cdb332b72761ed6441cd9 SHA-256: 320592aa53514c7fd425f4c691e4be802ca964955d5a6fdd960a8725c36737b4
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 with decoded Equation Editor payload, indicating a likely exploit. The ".objupdate" heuristic suggests that the OLE object is activated automatically upon opening the document. This points to a classic exploit delivery mechanism targeting the Equation Editor vulnerability.

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_off00000067.bin
aa9d8ca1f1c8f1a02059f3815f1a76c5d30d2f3f1510e991265e0d791475989b
rtf-objdata-decoded RTF \objdata at offset 0x67 269479 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.