Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 e247c77abacf660f…

MALICIOUS

RTF / .DOC

131.2 KB
MD5: ac409fd0dbdd1744e7196c6c9f5521ef SHA-1: 07ae696e3bc7c7732c014eecc2874f883d542900 SHA-256: e247c77abacf660fe4d310507a9d3481fbb993b95bf361eacd3265790fc0ad22
122 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The RTF file contains an embedded OLE object that decodes to a PE file, indicating an exploit targeting the Equation Editor. The ".objupdate" heuristic suggests that the OLE object is activated automatically upon opening the document, leading to the execution of the embedded payload. The decoded object is a suspicious artifact, likely a second-stage downloader or payload.

Heuristics 4

  • 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_off00000042.bin
4868801e6e51ce3b1babe9543cb56b6dc71ccb7658dd7864ac423c4d5e2618a7
rtf-objdata-decoded RTF \objdata at offset 0x42 67023 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.