Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 09badd6aa9fd4eb5…

MALICIOUS

RTF / .DOC

830.9 KB
MD5: 63ca785bc2e86add3b3fee0d64f2c998 SHA-1: d96b0a10889480451774d431cb0beba7982bebfc SHA-256: 09badd6aa9fd4eb5cee4ad27fc4233743259e86ddb74387bb4e920621a9f87bf
222 Risk Score

Malware Insights

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

The RTF file contains an OLE object related to Equation Editor, specifically triggering the CVE-2017-11882 vulnerability. This exploit is designed to execute a second-stage payload, likely a downloader or dropper, upon opening the document. The presence of the OLE object and the specific CVE strongly indicate a client-side exploitation attempt.

Heuristics 6

  • Equation Editor OLE1 native payload — CVE-2017-11882 related critical CVE related CVE_2017_11882_RELATED
    RTF decodes to an OLE1 Equation.3 embedded object whose native data is large and payload-like, and \objupdate requests automatic activation. This is the delivery shape used by Equation Editor RCE documents such as CVE-2017-11882/CVE-2018-0802, but the malformed MTEF record needed for exact attribution was not recovered.
  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • 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.
  • OLE object data medium RTF_OBJDATA
    RTF contains 1 \objdata section(s) — embedded OLE objects
  • Suspicious extracted artifact info 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000077.bin
aea3fc8a8f79208838e48e30f27126b114cb2fd5db03ca84b36b39530299d181
rtf-objdata-decoded RTF \objdata at offset 0x77 425269 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.