Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 1c70e60494e8059a…

MALICIOUS

RTF / .DOC

308.8 KB
MD5: 17a70405e014705d7eb3ad43ef4353aa SHA-1: 1d763a2276e5df4267f376c9aedbfbf5b7235e1d SHA-256: 1c70e60494e8059af11102d90b6495c330a9eed9efc564198d3fbca54fbf2af9
122 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The sample is an RTF document that contains an embedded OLE object, specifically targeting the Equation Editor vulnerability. The ".objupdate" heuristic indicates that the OLE object is designed to be activated automatically, leading to the execution of a decoded PE file. This strongly suggests a malicious document designed to exploit this known vulnerability for initial access.

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_off00000596.bin
59976ade99d3e61cc4dc54a3f365cd9004a93d063e11f0fe19497a3d5491de17
rtf-objdata-decoded RTF \objdata at offset 0x596 157080 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.