Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 49bdadc2330d8b62…

MALICIOUS

RTF / .DOC

830.8 KB
MD5: 603385849b59e05562d32f4b8caa0328 SHA-1: 0d37bd1292748ff51ab2302856d962e5fde7c04e SHA-256: 49bdadc2330d8b62ca0bc5f4383352d25d11b1a4afe9b71e7ce5e6f10ff5c17c
122 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File Execution T1204.002 Malicious File Execution: User Execution: Malicious File

The RTF file contains an embedded OLE object that decodes to a PE file, indicating a likely exploit targeting the Equation Editor. The ".objupdate" heuristic suggests that the OLE object is automatically activated upon opening the document. The decoded artifact, objdata_00_off00000044.bin, is highly suspicious and likely contains the secondary payload. The overall attack pattern is consistent with exploiting a known vulnerability to deliver further malicious content.

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_off00000044.bin
9dd4383616d8b6ac4e2085be6d8ddd90f077e08e4c02ff030853b52a5e97d098
rtf-objdata-decoded RTF \objdata at offset 0x44 425253 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.