Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 7d87a240aebb468e…

MALICIOUS

RTF / .DOC

475.1 KB
MD5: 85501a66797907eca8e3eefb91e53d85 SHA-1: 7113cecdff303bf2b54118febfe6561d9a895d5c SHA-256: 7d87a240aebb468e295dbb43f45ab8989f78567d5869fa6365f1d94c42a10dbe
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 with decoded Equation Editor payload, indicating a likely exploit. The ".objupdate" heuristic suggests that the OLE object is automatically activated upon opening the document, leading to the execution of the embedded Portable Executable (PE) file. This is a common delivery mechanism for malware.

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_off00000063.bin
9d19af013fd5ff52907586e770867f380b4daec112b1ecd998b8cd9a24b1099d
rtf-objdata-decoded RTF \objdata at offset 0x63 243033 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.