Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 4ab5c64d9f00a60a…

MALICIOUS

RTF / .DOC

86.3 KB
MD5: 457ae195d62a65dc40f8ef63d72be59c SHA-1: b7f89aad8684765189caab465cac492893f10a74 SHA-256: 4ab5c64d9f00a60ae868b1020e5d37c5b324b3bc5f65b14a9fe48475b6b54ccd
122 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The RTF document contains an embedded OLE object with decoded Equation Editor payload, indicating an exploit targeting this component. The ".objupdate" directive suggests that the embedded object is automatically activated upon opening the document, leading to the execution of the malicious payload. The presence of a PE file within the decoded object further confirms the malicious intent.

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_off0000004b.bin
f8138cb11afa275e5a604820f457874164137bb7da65513c85bf98078881e85f
rtf-objdata-decoded RTF \objdata at offset 0x4B 44045 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.