Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 e5e9fe5fa93f90c1…

MALICIOUS

RTF / .DOC

223.6 KB First seen: 2022-07-21
MD5: 30cb7761b20db96fa942f070271d23bc SHA-1: b7857795ab423451d7d196f7e0e45b741b75b0eb SHA-256: e5e9fe5fa93f90c1a511b3c82612c51eb96260e78186b60ad9b21c4df4e8bc5d
200 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution T1559.002 Component Object Model Hijacking

The RTF document contains OLE objects with composite monikers, which are indicative of the CVE-2017-8570 vulnerability. This vulnerability allows for the dropping and execution of a script, likely a second-stage payload. The embedded OLE objects and the specific heuristic firings strongly suggest this attack vector.

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_off000007d2.bin
7900a6aae9f6bcbf65c3faa6dfc12545e51e25ac893724431f8f03a39a3595b3
rtf-objdata-decoded RTF \objdata at offset 0x7D2 18697 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 shell/COM execution token(s).
objdata_01_off0000a05a.bin
3c97121fe02f90da16cb2983b3ae893ea40de52f15d26984fbdbae19aab20ebc
rtf-objdata-decoded RTF \objdata at offset 0xA05A 2632 bytes
objdata_02_off0000b5fd.bin
142dc43284d9abe994719f8fb67bc4c04bfc3f07528a1a66b0bad7e552ee8e78
rtf-objdata-decoded RTF \objdata at offset 0xB5FD 12297 bytes