Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 54b0ff9d62ef4867…

MALICIOUS

RTF / .DOC

346.9 KB First seen: 2021-06-20
MD5: 46e530bd1d4af9fb8a4524642243161b SHA-1: 6c0b5e411be5c9063ed0132bb66924ae257fe1ed SHA-256: 54b0ff9d62ef4867ba3aea9daa53c21a2b9e7ed772504e960bfc1d568ecb3850
320 Risk Score

Malware Insights

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

The RTF document contains multiple OLE objects, with high-confidence heuristics indicating automatic linking and update triggers. These mechanisms are commonly used to embed and execute malicious code, likely leading to the download or execution of a secondary payload. No document body text or scripts were extracted, limiting further analysis of the specific payload.

Heuristics 8

  • 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.
  • CVE-2017-0199 / CVE-2017-8759 (OLE2Link auto-activated remote loader) critical CVE related RTF_OLE2LINK_REMOTE_MONIKER_LOADER
    RTF embeds an OLE2Link object that is force-activated with \objupdate (no user interaction on open) and fetches a remote second stage — through an INCLUDETEXT/INCLUDEPICTURE field or the OLE object's own moniker. This is the OLE2Link auto-update attack path shared by CVE-2017-0199 (server returns an HTA/scriptlet) and CVE-2017-8759 (server returns a SOAP WSDL the .NET parser compiles). Office processes the fetched response through the same code path; the specific CVE depends on the now-unreachable server content type.
  • 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.
  • 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.
  • Suspicious extracted artifact high 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.
  • OLE object data medium RTF_OBJDATA
    RTF contains 4 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
🗂 Part of campaign: shared payload 3cd3b7d42e 51 samples

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000007da.bin rtf-objdata-decoded RTF \objdata at offset 0x7DA 65990 bytes
SHA-256: 40b762f177e5753d6be0efff916c9cd4bf88fd43733ffc145cd0ff205c8d690c
objdata_01_off00006f89.bin rtf-objdata-decoded RTF \objdata at offset 0x6F89 65963 bytes
SHA-256: bb6cd5a22c60cb4918dacd8693eb22185a032e038b501a9d993c2ef274a9985e
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): WScript.Shell"")")
objdata_02_off0002881c.bin rtf-objdata-decoded RTF \objdata at offset 0x2881C 2632 bytes
SHA-256: 32e8e449cdc043249ce37c79c9eaf2af80a02cb8175718a8a0ce726d961b7d16
objdata_03_off00029dbf.bin rtf-objdata-decoded RTF \objdata at offset 0x29DBF 12297 bytes
SHA-256: e8d4fe950caed6dcfde26f4b616825bbe11b93458425974b7d075167f675abf7