Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 657ad1e8c17b8ac6…

MALICIOUS

RTF / .DOC

232.9 KB First seen: 2022-06-24
MD5: 22900d6f2b8f86dcc9bb04f6cb047710 SHA-1: 7253a2f5d863d5a1b78de74c294b9a6e25708d92 SHA-256: 657ad1e8c17b8ac6846b81f45e8fa390c3e3a68e459a240ebecbb0a562e7ed14
220 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The RTF document contains embedded OLE objects and triggers CVE-2017-8570, which is known to drop SCT scripts. The document body explicitly instructs the user to 'click Enable Editing when opening', indicating a lure to bypass macro security. The embedded artifacts, particularly objdata_01_off0000c5c3.bin, are associated with the CVE and likely contain the malicious script.

Heuristics 7

  • 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
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • 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_off0000095d.bin
0da2fd4ff5e63075aeeb3b313c0a97e46d347d6fe330d889cb564271d9f8aa4d
rtf-objdata-decoded RTF \objdata at offset 0x95D 23112 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 shell/COM execution token(s).
objdata_01_off0000c5c3.bin
625ba87dad062d63542a2f08013c93a4f9eac2363a88c9240f1688e698b82c02
rtf-objdata-decoded RTF \objdata at offset 0xC5C3 2632 bytes
objdata_02_off0000db66.bin
142dc43284d9abe994719f8fb67bc4c04bfc3f07528a1a66b0bad7e552ee8e78
rtf-objdata-decoded RTF \objdata at offset 0xDB66 12297 bytes