Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d7ed7573c73df4a0…

MALICIOUS

RTF / .DOC

1.14 MB First seen: 2023-08-30
MD5: d878b97d3171dd1015b4d4ed9f41101a SHA-1: 388c291ae8bd4dff02fad1377a1a363abcbfe5b0 SHA-256: d7ed7573c73df4a00a5479906dceaf244b507d4db2a8ab8a8e99e8733170c8cd
122 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1027 Obfuscated Files or Information

The RTF document contains a large amount of hex-encoded data within an OLE object, indicated by RTF_EXCESSIVE_HEX and RTF_OBJDATA heuristics. The RTF_OBJUPDATE heuristic suggests that this embedded object is designed to be activated, likely triggering an exploit. The presence of a large, suspicious binary artifact further supports the conclusion that this document is a malicious loader.

Heuristics 5

  • \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.
  • Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX
    RTF contains ~1193KB of hex-encoded data inside \objdata sections — may hide a payload
  • OLE object data medium RTF_OBJDATA
    RTF contains 1 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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_off00000089.bin
4013f84062cd5c23a474957e706f55ebe3dc310d6d6db388b34eacb09fa32626
rtf-objdata-decoded RTF \objdata at offset 0x89 596692 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.