Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 07a7c9a2e1cfa993…

MALICIOUS

RTF / .DOC

325.1 KB
MD5: 508243f1ac9630c24ba2e2075a79dd69 SHA-1: 34414b0929b642e7d6ec0503eaa1a39370c011d0 SHA-256: 07a7c9a2e1cfa993138d4e7dd1d2cbe608a99b9d701a156182c0ed20dafbffa7
182 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object that exploits the CVE-2017-11882 vulnerability in Microsoft Equation Editor. This exploit is designed to decode and execute a secondary payload, likely a PE file, which is indicated by the 'RTF_EQUATION_EDITOR' and 'CVE_2017_11882_RELATED' heuristic firings. The presence of an OLE object and the specific CVE strongly suggest an attack pattern involving exploitation for client execution, often delivered via spearphishing attachments.

Heuristics 5

  • 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.
  • Decoded Equation Editor payload + PE critical RTF_EQUATION_EDITOR
    RTF decodes to an Equation Editor ProgID adjacent to OLE activation and the same decoded object stream contains embedded PE bytes. This matches the Equation Editor exploit surface used by CVE-2017-11882 / CVE-2018-0802 documents, while requiring payload evidence to avoid flagging benign Equation references.
  • \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_off00000043.bin
4f4e5a4a8e9b1ed8226ced6d86aef1e89a16767c596c810a613854b4b531943e
rtf-objdata-decoded RTF \objdata at offset 0x43 166307 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.