Malicious RTF — malware analysis report

Static analysis result for SHA-256 ee66911f622eb6de…

MALICIOUS

RTF

229.4 KB First seen: 2022-07-15
MD5: 50f0125f5a86cf128a56bb09774fe1c1 SHA-1: 4cbf005bf5fa18a73f4ad13933b96609cf17c748 SHA-256: ee66911f622eb6de95bb4323f1f8d858b0bccba192ebc4eeefa2bcde4726b9c7
200 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File Execution T1059 Command and Scripting Interpreter

The RTF file contains embedded OLE objects and triggers ".objupdate" which are indicative of exploitation. Specifically, the "CVE_2017_8570" heuristic firing points to the use of a Composite Moniker to drop an SCT script. This mechanism is commonly used to execute arbitrary code, likely to download and run a second-stage payload.

Heuristics 6

  • Composite Moniker — CVE-2017-8570 (drops SCT script) critical CVE related CVE_2017_8570
    RTF \objdata decodes to OLE data containing the Composite Moniker — CVE-2017-8570 (drops SCT script) CLSID — the vulnerable control/moniker is embedded directly in the document's object stream, the delivery shape of this exploit. RTF objects auto-render when Word opens the file.
  • Composite Moniker in RTF OLE object high CVE related RTF_COMPOSITE_MONIKER_RELATED
    RTF contains Composite Moniker CLSID in OLE object context, but no nearby scriptlet/SCT payload was confirmed. Treat as related moniker attack-surface evidence rather than proof of CVE-2017-8570 exploitation.
  • \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 3 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • Suspicious extracted artifact medium 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000007d1.bin
f9b6f7da3318c48c4d7b1e29cbff4bf96180eb3f748ce73c659c3c1e6703760c
rtf-objdata-decoded RTF \objdata at offset 0x7D1 21569 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 shell/COM execution token(s).
objdata_01_off0000b7af.bin
0f2cec052fe8f824845b1aa6e0804ad719eb3010400f0023038dbc39515992c2
rtf-objdata-decoded RTF \objdata at offset 0xB7AF 2632 bytes
objdata_02_off0000cd52.bin
142dc43284d9abe994719f8fb67bc4c04bfc3f07528a1a66b0bad7e552ee8e78
rtf-objdata-decoded RTF \objdata at offset 0xCD52 12297 bytes