Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 da99a459ebea6afd…

MALICIOUS

RTF / .DOC

244.1 KB First seen: 2023-04-18
MD5: 9b7e9d8c1fb5b68e7c65cd753a0f4839 SHA-1: a339e65ceb0f5209d5e4b2e57c47e4b238f0cc8a SHA-256: da99a459ebea6afd93adef1efbea4c6195f509b727c37ddd928ddb6cda0d3c3d
102 Risk Score

Malware Insights

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

The sample is an RTF document containing embedded OLE object data, indicated by the RTF_OBJDATA heuristic. The RTF_OBJAUTLINK and RTF_OBJUPDATE heuristics suggest that this OLE object is automatically activated upon opening the document. This mechanism is commonly used to execute embedded malicious code or download and run a secondary payload, hence the high confidence in an attack pattern involving OLE object exploitation.

Heuristics 4

  • 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_off00000098.bin
e7ff15ae4bd0db4b7f5e9001b5afc765fc63d10c0a482eb13906bb27c6dea42a
rtf-objdata-decoded RTF \objdata at offset 0x98 124881 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.