Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 c7ca6ef5dcd26c5d…

MALICIOUS

RTF / .DOC

223.6 KB First seen: 2022-07-29
MD5: ede4d84b20f1f8cbbc82ea0ae560a4fc SHA-1: 66b5e48f4aa896e41b9135c879b73ede02d2f351 SHA-256: c7ca6ef5dcd26c5d756218edfda9dd5d1b7d70bb2ec77d0f1cc0c6ae9c88257e
200 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1559.002 Component Object Model Hijacking T1140 Deobfuscate/Decode Files or Information

The RTF document contains embedded OLE objects, specifically triggering the CVE-2017-8570 vulnerability. This vulnerability allows for the execution of a script, likely a second-stage payload, by exploiting a composite moniker. The embedded object data is decoded and signals indicate script execution terms.

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
68187a3cde0142a944bdb636af3338037136e176dda1e55945728b87f4e6133f
rtf-objdata-decoded RTF \objdata at offset 0x7D2 18718 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 shell/COM execution token(s).
objdata_01_off0000a086.bin
3c97121fe02f90da16cb2983b3ae893ea40de52f15d26984fbdbae19aab20ebc
rtf-objdata-decoded RTF \objdata at offset 0xA086 2632 bytes
objdata_02_off0000b629.bin
142dc43284d9abe994719f8fb67bc4c04bfc3f07528a1a66b0bad7e552ee8e78
rtf-objdata-decoded RTF \objdata at offset 0xB629 12297 bytes