Malicious RTF — malware analysis report

Static analysis result for SHA-256 48630e72b3a3dfae…

MALICIOUS

RTF

313.0 KB
MD5: 711576fd2bb01198df0a5db9fe9641e2 SHA-1: 12c717b25c918edc1b07af52e67a80b9293901d6 SHA-256: 48630e72b3a3dfae2043394e8f615ecdf757ca7ad89b0eacbabc4176cd1cece4
122 Risk Score

Malware Insights

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

The RTF file contains OLE object data, specifically a decoded Equation Editor payload. The \objupdate directive indicates that this object is designed to be activated, triggering the execution of the embedded PE file. This strongly suggests a malicious document designed to exploit the Equation Editor vulnerability to download and run a secondary 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_off0000174c.bin
1e4b7da7fbf47d74fe82ee84a80866fc87c380d52aa127b594b2a1c4767b9a6a
rtf-objdata-decoded RTF \objdata at offset 0x174C 157189 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.