Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 ee2d6c19861f5b8c…

MALICIOUS

RTF / .DOC

1.14 MB First seen: 2023-09-13
MD5: 35571d4b9b3317c166365df3d3c70ed4 SHA-1: 8541741e240ed8ca368096be7bf4217aef0b2452 SHA-256: ee2d6c19861f5b8c94657284c2826aca0da64a75c10e369f0f93cd9d9d124f4f
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 OLE object with excessive hex-encoded data, strongly suggesting it is designed to exploit a vulnerability upon activation. The presence of `RTF_OBJUPDATE` indicates an attempt to force OLE activation, likely to trigger an embedded exploit. The extracted artifact `objdata_00_off0000008a.bin` is suspicious due to its size and high entropy, further supporting the hypothesis of a hidden payload.

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 ~1194KB 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_off0000008a.bin
5f130d1daddd31545237aa36808373554a53ae5a7103a2b781d48531b671aee6
rtf-objdata-decoded RTF \objdata at offset 0x8A 597042 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.